<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Agent Systems in Plain English Series on Peter Fulop</title><link>https://peterfulop.tech/tags/agent-systems-in-plain-english-series/</link><description>Recent content in Agent Systems in Plain English Series on Peter Fulop</description><generator>Hugo -- gohugo.io</generator><language>en-us</language><copyright>Peter Fulop</copyright><lastBuildDate>Wed, 08 Apr 2026 00:00:00 +0000</lastBuildDate><atom:link href="https://peterfulop.tech/tags/agent-systems-in-plain-english-series/index.xml" rel="self" type="application/rss+xml"/><item><title>In agent systems, context matters more than the prompt</title><link>https://peterfulop.tech/p/in-agent-systems-context-matters-more-than-the-prompt/</link><pubDate>Wed, 08 Apr 2026 00:00:00 +0000</pubDate><guid>https://peterfulop.tech/p/in-agent-systems-context-matters-more-than-the-prompt/</guid><description>&lt;img src="https://peterfulop.tech/p/in-agent-systems-context-matters-more-than-the-prompt/in-agent-systems-context-matters-more-than-the-prompt.png" alt="Featured image of post In agent systems, context matters more than the prompt" /&gt;&lt;p&gt;This is the second post in a series called &amp;ldquo;Agent systems in plain English,&amp;rdquo; where I try to make agent systems easier to reason about in practical terms. In this post, I focus on context: the full run input the planner sees when it is choosing the next step.&lt;/p&gt;
&lt;p&gt;If the model is allowed to choose the next step, what exactly does it see before it chooses?&lt;/p&gt;
&lt;p&gt;I think people often talk about &amp;ldquo;prompt engineering&amp;rdquo; as if the prompt were the whole object. It is not.&lt;/p&gt;
&lt;p&gt;Anthropic&amp;rsquo;s September 29, 2025 post &lt;a class="link" href="https://www.anthropic.com/engineering/effective-context-engineering-for-ai-agents" target="_blank" rel="noopener"
&gt;&amp;ldquo;Effective context engineering for AI agents&amp;rdquo;&lt;/a&gt; frames the distinction clearly: the planner does not see &amp;ldquo;the prompt.&amp;rdquo; It sees the whole token budget for that run. &lt;a class="link" href="https://docs.openclaw.ai/concepts/context" target="_blank" rel="noopener"
&gt;OpenClaw&amp;rsquo;s current context docs&lt;/a&gt; make the same point from the runtime side. Context is everything the system sends to the model for a run, bounded by the current context window, the finite token budget the model can attend to in a single run.&lt;/p&gt;
&lt;blockquote&gt;
&lt;p&gt;The planner&amp;rsquo;s input is the full run context. The prompt is only one slice of it.&lt;/p&gt;
&lt;/blockquote&gt;
&lt;p&gt;If the previous post, titled &lt;a class="link" href="https://peterfulop.tech/p/agents-in-plain-english-for-developers/" target="_blank" rel="noopener"
&gt;Agents in plain English for developers&lt;/a&gt; asked &amp;ldquo;who owns the next step?&amp;rdquo;, post 2 asks the follow-up question: how is that input assembled?&lt;/p&gt;
&lt;p&gt;This post is specifically about tool-using agent systems where the model is choosing the next step.&lt;/p&gt;
&lt;p&gt;Here, &amp;ldquo;planner&amp;rdquo; just means the model as used for next-step choice, and &amp;ldquo;runtime&amp;rdquo; means the host system that assembles context, exposes tools, and enforces limits.&lt;/p&gt;
&lt;h2 id="context-is-not-just-the-prompt"&gt;Context is not just the prompt
&lt;/h2&gt;&lt;p&gt;At the API level, an LLM call is &lt;a class="link" href="https://medium.com/genai-llms/llms-are-stateless-context-is-the-product-336c50ae637c" target="_blank" rel="noopener"
&gt;effectively stateless&lt;/a&gt;. Across calls, it only knows what the runtime sends for this run.&lt;/p&gt;
&lt;p&gt;That usually includes more than people think, including few-shot examples, meaning small input/output demonstrations shown in the prompt:&lt;/p&gt;
&lt;table&gt;
&lt;thead&gt;
&lt;tr&gt;
&lt;th&gt;Part of the run&lt;/th&gt;
&lt;th&gt;Usually visible to you?&lt;/th&gt;
&lt;th&gt;Counts toward the window?&lt;/th&gt;
&lt;/tr&gt;
&lt;/thead&gt;
&lt;tbody&gt;
&lt;tr&gt;
&lt;td&gt;System prompt&lt;/td&gt;
&lt;td&gt;partly&lt;/td&gt;
&lt;td&gt;yes&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td&gt;Few-shot examples&lt;/td&gt;
&lt;td&gt;yes&lt;/td&gt;
&lt;td&gt;yes&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td&gt;Conversation history&lt;/td&gt;
&lt;td&gt;yes&lt;/td&gt;
&lt;td&gt;yes&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td&gt;Tool calls and tool results&lt;/td&gt;
&lt;td&gt;yes&lt;/td&gt;
&lt;td&gt;yes&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td&gt;Injected files or workspace snippets&lt;/td&gt;
&lt;td&gt;sometimes&lt;/td&gt;
&lt;td&gt;yes&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td&gt;Tool schemas&lt;/td&gt;
&lt;td&gt;often not as plain text&lt;/td&gt;
&lt;td&gt;yes&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td&gt;Provider-added wrappers or hidden headers&lt;/td&gt;
&lt;td&gt;often not visible&lt;/td&gt;
&lt;td&gt;yes&lt;/td&gt;
&lt;/tr&gt;
&lt;/tbody&gt;
&lt;/table&gt;
&lt;p&gt;&lt;a class="link" href="https://docs.openclaw.ai/concepts/context" target="_blank" rel="noopener"
&gt;OpenClaw&amp;rsquo;s context docs&lt;/a&gt; explicitly note that provider wrappers or hidden headers still count even when you do not see them directly. Invisible tokens still consume budget.&lt;/p&gt;
&lt;p&gt;Prompting still matters. It is just one slice of the assembled input. Files, examples, tool definitions, tool results, and runtime-added wrappers all compete for the same finite window.&lt;/p&gt;
&lt;h2 id="bigger-context-is-not-automatically-better-context"&gt;Bigger context is not automatically better context
&lt;/h2&gt;&lt;p&gt;A common instinct here is: if some context helps, more context should help more. Sometimes that works briefly. Then it starts &lt;a class="link" href="https://eval.16x.engineer/blog/llm-context-management-guide" target="_blank" rel="noopener"
&gt;failing in familiar ways&lt;/a&gt;.&lt;/p&gt;
&lt;p&gt;Too much context often creates at least four problems:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;it dilutes the signal&lt;/li&gt;
&lt;li&gt;it creates more irrelevant choices&lt;/li&gt;
&lt;li&gt;it makes tool selection murkier&lt;/li&gt;
&lt;li&gt;it raises the cost of every turn&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;The issue is not just token cost. In many cases, the more important cost is decision quality. If you give the planner three similar tools, one stale incident note, and an example that fits the wrong checkout failure, you are not really informing it. You are making action selection harder.&lt;/p&gt;
&lt;p&gt;I think the better question is not &amp;ldquo;how much context can I fit?&amp;rdquo; but &amp;ldquo;what is the smallest useful context for this task?&amp;rdquo;&lt;/p&gt;
&lt;h2 id="context-is-not-memory"&gt;Context is not memory
&lt;/h2&gt;&lt;p&gt;Context is what is inside the model&amp;rsquo;s current window for this run. Memory is what you may store somewhere else and decide to reload later.&lt;/p&gt;
&lt;p&gt;&lt;a class="link" href="https://docs.openclaw.ai/concepts/context" target="_blank" rel="noopener"
&gt;OpenClaw&amp;rsquo;s context docs&lt;/a&gt; are very clear on this distinction: memory may live on disk and be reloaded later; context is what is actually inside the model window now.&lt;/p&gt;
&lt;p&gt;That distinction matters because &amp;ldquo;memory&amp;rdquo; often ends up meaning &amp;ldquo;we pasted old things back into the next run.&amp;rdquo; The result is not memory. It is clutter.&lt;/p&gt;
&lt;p&gt;We will cover this topic in more detail later in another blog post. For now, a useful rule is simpler: if you cannot explain why a piece of information belongs in the current run, it probably does not belong there.&lt;/p&gt;
&lt;h2 id="a-minimal-setup"&gt;A minimal setup
&lt;/h2&gt;&lt;p&gt;If you need &lt;code&gt;uv&lt;/code&gt;, PEP 723, or free API access routes, see the previous post, &lt;a class="link" href="https://peterfulop.tech/p/agents-in-plain-english-for-developers/" target="_blank" rel="noopener"
&gt;Agents in plain English for developers&lt;/a&gt;. For this post, the only thing you need to know is that the script below is ordinary Python 3.11+ and runs with &lt;code&gt;uv run&lt;/code&gt;. If no API key is set, it still works locally because it prints the assembled contexts.&lt;/p&gt;
&lt;h2 id="a-small-context-builder"&gt;A small context builder
&lt;/h2&gt;&lt;p&gt;This example builds two contexts for the same task:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;a lean context with the right files, one clean reference example, and two clearly scoped tools&lt;/li&gt;
&lt;li&gt;a bloated context with a stale but tempting incident note, a misaligned example, and broader tools that invite the wrong move&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;The important part is not just that the second profile is longer. It gives the model more ways to get pulled off course.
In this post, those tools are only definitions inside the assembled context. &lt;strong&gt;Nothing executes yet&lt;/strong&gt;; the host-side tool loop comes later.&lt;/p&gt;
&lt;p&gt;If you want the commands exactly as written, call this file &lt;code&gt;context_builder.py&lt;/code&gt;:&lt;/p&gt;
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&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-python" data-lang="python"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="ch"&gt;#!/usr/bin/env python3&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# /// script&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# requires-python = &amp;#34;&amp;gt;=3.11&amp;#34;&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# ///&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="kn"&gt;from&lt;/span&gt; &lt;span class="nn"&gt;__future__&lt;/span&gt; &lt;span class="kn"&gt;import&lt;/span&gt; &lt;span class="n"&gt;annotations&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="kn"&gt;import&lt;/span&gt; &lt;span class="nn"&gt;json&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="n"&gt;FILES&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;checkout_spec.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Checkout must preserve cart state and open the payment sheet.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;router_notes.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;The iOS white screen started after replacing push_checkout_screen() with replace(&amp;#39;/checkout&amp;#39;). Inspect route replacement and state handoff.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;migration_incident_2024.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;During the 2024 payment-provider migration, blank checkout screens usually came from missing STRIPE_PUBLIC_KEY. Search env wiring before UI routes.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;support_macros.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Start by apologizing, asking for a screenshot, and suggesting a reinstall if needed.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="n"&gt;TOOLS&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;lean&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;read_file&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Read one provided file by name.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;finish_json&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Return only JSON with probable_root_cause and next_file_to_read.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;bloated&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;read_file&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Read one provided file by name.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;search_repo&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Search broadly for anything related to the symptom, env keys, or past fixes.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;open_incident_log&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Open an older incident note that may describe a similar checkout failure.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;finish_json&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Return only JSON with probable_root_cause and next_file_to_read.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="n"&gt;EXAMPLES&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;lean&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;white screen on checkout after router rewrite&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s1"&gt;&amp;#39;{&amp;#34;probable_root_cause&amp;#34;:&amp;#34;router state handoff regression&amp;#34;,&amp;#34;next_file_to_read&amp;#34;:&amp;#34;router_notes.txt&amp;#34;}&amp;#39;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;bloated&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;white screen on checkout after router rewrite&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s1"&gt;&amp;#39;{&amp;#34;probable_root_cause&amp;#34;:&amp;#34;router state handoff regression&amp;#34;,&amp;#34;next_file_to_read&amp;#34;:&amp;#34;router_notes.txt&amp;#34;}&amp;#39;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;blank checkout after provider upgrade&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s1"&gt;&amp;#39;{&amp;#34;probable_root_cause&amp;#34;:&amp;#34;missing payment provider key&amp;#34;,&amp;#34;next_file_to_read&amp;#34;:&amp;#34;migration_incident_2024.txt&amp;#34;}&amp;#39;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="k"&gt;def&lt;/span&gt; &lt;span class="nf"&gt;build_context&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;task&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;profile&lt;/span&gt;&lt;span class="p"&gt;):&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;files&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;checkout_spec.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;router_notes.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;profile&lt;/span&gt; &lt;span class="o"&gt;==&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;lean&amp;#34;&lt;/span&gt; &lt;span class="k"&gt;else&lt;/span&gt; &lt;span class="nb"&gt;list&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;FILES&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;tools&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;TOOLS&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="n"&gt;profile&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;examples&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;EXAMPLES&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="n"&gt;profile&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;prompt&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="se"&gt;\n\n&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;join&lt;/span&gt;&lt;span class="p"&gt;([&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;You are a debugging assistant. Answer only from the provided context.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="sa"&gt;f&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;Task: &lt;/span&gt;&lt;span class="si"&gt;{&lt;/span&gt;&lt;span class="n"&gt;task&lt;/span&gt;&lt;span class="si"&gt;}&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;Available tools:&lt;/span&gt;&lt;span class="se"&gt;\n&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt; &lt;span class="o"&gt;+&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="se"&gt;\n&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;join&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="sa"&gt;f&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;- &lt;/span&gt;&lt;span class="si"&gt;{&lt;/span&gt;&lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="si"&gt;}&lt;/span&gt;&lt;span class="s2"&gt;: &lt;/span&gt;&lt;span class="si"&gt;{&lt;/span&gt;&lt;span class="n"&gt;desc&lt;/span&gt;&lt;span class="si"&gt;}&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt; &lt;span class="k"&gt;for&lt;/span&gt; &lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;desc&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;tools&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;Examples:&lt;/span&gt;&lt;span class="se"&gt;\n&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt; &lt;span class="o"&gt;+&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="se"&gt;\n&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;join&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="sa"&gt;f&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;Input: &lt;/span&gt;&lt;span class="si"&gt;{&lt;/span&gt;&lt;span class="n"&gt;inp&lt;/span&gt;&lt;span class="si"&gt;}&lt;/span&gt;&lt;span class="se"&gt;\n&lt;/span&gt;&lt;span class="s2"&gt;Output: &lt;/span&gt;&lt;span class="si"&gt;{&lt;/span&gt;&lt;span class="n"&gt;out&lt;/span&gt;&lt;span class="si"&gt;}&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt; &lt;span class="k"&gt;for&lt;/span&gt; &lt;span class="n"&gt;inp&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;out&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;examples&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;Files:&lt;/span&gt;&lt;span class="se"&gt;\n&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt; &lt;span class="o"&gt;+&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="se"&gt;\n&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;join&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="sa"&gt;f&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;## &lt;/span&gt;&lt;span class="si"&gt;{&lt;/span&gt;&lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="si"&gt;}&lt;/span&gt;&lt;span class="se"&gt;\n&lt;/span&gt;&lt;span class="si"&gt;{&lt;/span&gt;&lt;span class="n"&gt;FILES&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;&lt;span class="si"&gt;}&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt; &lt;span class="k"&gt;for&lt;/span&gt; &lt;span class="n"&gt;name&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;files&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;])&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;profile&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;profile&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;files&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;files&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;tools&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="n"&gt;name&lt;/span&gt; &lt;span class="k"&gt;for&lt;/span&gt; &lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;_&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;tools&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;example_count&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="nb"&gt;len&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;examples&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;prompt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;prompt&lt;/span&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="n"&gt;task&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Explain the likely checkout bug and name the next file to inspect.&amp;#34;&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="k"&gt;for&lt;/span&gt; &lt;span class="n"&gt;profile&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;lean&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;bloated&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;):&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;payload&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;build_context&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;task&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;profile&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nb"&gt;print&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;json&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;dumps&lt;/span&gt;&lt;span class="p"&gt;({&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;profile&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;payload&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;profile&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;files&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;payload&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;files&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;tools&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;payload&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;tools&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;example_count&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;payload&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;example_count&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;chars&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="nb"&gt;len&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;payload&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;prompt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;prompt_preview&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;payload&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;prompt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;][:&lt;/span&gt;&lt;span class="mi"&gt;220&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt; &lt;span class="o"&gt;+&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;...&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;},&lt;/span&gt; &lt;span class="n"&gt;indent&lt;/span&gt;&lt;span class="o"&gt;=&lt;/span&gt;&lt;span class="mi"&gt;2&lt;/span&gt;&lt;span class="p"&gt;))&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;Run it:&lt;/p&gt;
&lt;div class="highlight"&gt;&lt;div class="chroma"&gt;
&lt;table class="lntable"&gt;&lt;tr&gt;&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code&gt;&lt;span class="lnt"&gt;1
&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;
&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-bash" data-lang="bash"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;uv run context_builder.py
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;Expected output sketch:&lt;/p&gt;
&lt;div class="highlight"&gt;&lt;div class="chroma"&gt;
&lt;table class="lntable"&gt;&lt;tr&gt;&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code&gt;&lt;span class="lnt"&gt; 1
&lt;/span&gt;&lt;span class="lnt"&gt; 2
&lt;/span&gt;&lt;span class="lnt"&gt; 3
&lt;/span&gt;&lt;span class="lnt"&gt; 4
&lt;/span&gt;&lt;span class="lnt"&gt; 5
&lt;/span&gt;&lt;span class="lnt"&gt; 6
&lt;/span&gt;&lt;span class="lnt"&gt; 7
&lt;/span&gt;&lt;span class="lnt"&gt; 8
&lt;/span&gt;&lt;span class="lnt"&gt; 9
&lt;/span&gt;&lt;span class="lnt"&gt;10
&lt;/span&gt;&lt;span class="lnt"&gt;11
&lt;/span&gt;&lt;span class="lnt"&gt;12
&lt;/span&gt;&lt;span class="lnt"&gt;13
&lt;/span&gt;&lt;span class="lnt"&gt;14
&lt;/span&gt;&lt;span class="lnt"&gt;15
&lt;/span&gt;&lt;span class="lnt"&gt;16
&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;
&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-json" data-lang="json"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;profile&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;lean&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;files&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;checkout_spec.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;router_notes.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;tools&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;read_file&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;finish_json&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;example_count&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="mi"&gt;1&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;chars&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="mi"&gt;706&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;prompt_preview&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;You are a debugging assistant...&amp;#34;&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;profile&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;bloated&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;files&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;checkout_spec.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;router_notes.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;migration_incident_2024.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;support_macros.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;tools&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;read_file&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;search_repo&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;open_incident_log&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;finish_json&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;example_count&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="mi"&gt;2&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;chars&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="mi"&gt;1337&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;prompt_preview&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;You are a debugging assistant...&amp;#34;&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;Even a tiny tool schema, the structured contract the model sees for a tool, starts adding context too:&lt;/p&gt;
&lt;div class="highlight"&gt;&lt;div class="chroma"&gt;
&lt;table class="lntable"&gt;&lt;tr&gt;&lt;td class="lntd"&gt;
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&lt;/span&gt;&lt;span class="lnt"&gt;5
&lt;/span&gt;&lt;span class="lnt"&gt;6
&lt;/span&gt;&lt;span class="lnt"&gt;7
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&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;
&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-json" data-lang="json"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;name&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;search_repo&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;description&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Search broadly for anything related to the symptom, env keys, or past fixes.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;input_schema&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;object&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;properties&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="nt"&gt;&amp;#34;query&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="nt"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;string&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;}},&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nt"&gt;&amp;#34;required&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;query&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;The same logic applies to any skill text or runtime metadata the host injects. If it is in the run, it spends tokens.&lt;/p&gt;
&lt;p&gt;Illustrative contrast, not guaranteed model output:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;lean: &lt;code&gt;{&amp;quot;probable_root_cause&amp;quot;:&amp;quot;router state handoff regression&amp;quot;,&amp;quot;next_file_to_read&amp;quot;:&amp;quot;router_notes.txt&amp;quot;}&lt;/code&gt;&lt;/li&gt;
&lt;li&gt;bloated: &lt;code&gt;{&amp;quot;probable_root_cause&amp;quot;:&amp;quot;missing payment provider key&amp;quot;,&amp;quot;next_file_to_read&amp;quot;:&amp;quot;migration_incident_2024.txt&amp;quot;}&lt;/code&gt;&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;Notice that the wrong answer is not random. It follows the stale file and the misaligned example.&lt;/p&gt;
&lt;p&gt;If you have an API key set, add a tiny model call and compare the answers:&lt;/p&gt;
&lt;div class="highlight"&gt;&lt;div class="chroma"&gt;
&lt;table class="lntable"&gt;&lt;tr&gt;&lt;td class="lntd"&gt;
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&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;
&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-python" data-lang="python"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="kn"&gt;import&lt;/span&gt; &lt;span class="nn"&gt;os&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="kn"&gt;from&lt;/span&gt; &lt;span class="nn"&gt;urllib&lt;/span&gt; &lt;span class="kn"&gt;import&lt;/span&gt; &lt;span class="n"&gt;request&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;os&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;getenv&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;OPENROUTER_API_KEY&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;):&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;for&lt;/span&gt; &lt;span class="n"&gt;profile&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;lean&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;bloated&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;):&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;payload&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;build_context&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;task&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;profile&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nb"&gt;print&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="sa"&gt;f&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;[&lt;/span&gt;&lt;span class="si"&gt;{&lt;/span&gt;&lt;span class="n"&gt;profile&lt;/span&gt;&lt;span class="si"&gt;}&lt;/span&gt;&lt;span class="s2"&gt;]&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;req&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;request&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;Request&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;https://openrouter.ai/api/v1/chat/completions&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;data&lt;/span&gt;&lt;span class="o"&gt;=&lt;/span&gt;&lt;span class="n"&gt;json&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;dumps&lt;/span&gt;&lt;span class="p"&gt;({&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;model&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;openrouter/free&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;temperature&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="mi"&gt;0&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;messages&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;role&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;user&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;content&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;payload&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;prompt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]}],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;})&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;encode&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;utf-8&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;headers&lt;/span&gt;&lt;span class="o"&gt;=&lt;/span&gt;&lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;Authorization&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="sa"&gt;f&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;Bearer &lt;/span&gt;&lt;span class="si"&gt;{&lt;/span&gt;&lt;span class="n"&gt;os&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;environ&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s1"&gt;&amp;#39;OPENROUTER_API_KEY&amp;#39;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;&lt;span class="si"&gt;}&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Content-Type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;application/json&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;},&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;)&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;with&lt;/span&gt; &lt;span class="n"&gt;request&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;urlopen&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;req&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;timeout&lt;/span&gt;&lt;span class="o"&gt;=&lt;/span&gt;&lt;span class="mi"&gt;60&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt; &lt;span class="k"&gt;as&lt;/span&gt; &lt;span class="n"&gt;response&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;body&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;json&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;loads&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;response&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;read&lt;/span&gt;&lt;span class="p"&gt;()&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;decode&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;utf-8&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;))&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="nb"&gt;print&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;body&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;choices&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="mi"&gt;0&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;message&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;content&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;strip&lt;/span&gt;&lt;span class="p"&gt;())&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;When I ran the fuller editor-side version of this example on March 28, 2026, this is what I got in one pass:&lt;/p&gt;
&lt;p&gt;OpenRouter:&lt;/p&gt;
&lt;div class="highlight"&gt;&lt;div class="chroma"&gt;
&lt;table class="lntable"&gt;&lt;tr&gt;&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code&gt;&lt;span class="lnt"&gt;1
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&lt;/span&gt;&lt;span class="lnt"&gt;4
&lt;/span&gt;&lt;span class="lnt"&gt;5
&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;
&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-json" data-lang="json"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="err"&gt;lean&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="nt"&gt;&amp;#34;probable_root_cause&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;router state handoff regression&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;&lt;span class="nt"&gt;&amp;#34;next_file_to_read&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;router_notes.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="err"&gt;bloated&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="nt"&gt;&amp;#34;probable_root_cause&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;missing payment provider key&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;&lt;span class="nt"&gt;&amp;#34;next_file_to_read&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;migration_incident_2024.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;Gemini:&lt;/p&gt;
&lt;div class="highlight"&gt;&lt;div class="chroma"&gt;
&lt;table class="lntable"&gt;&lt;tr&gt;&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code&gt;&lt;span class="lnt"&gt;1
&lt;/span&gt;&lt;span class="lnt"&gt;2
&lt;/span&gt;&lt;span class="lnt"&gt;3
&lt;/span&gt;&lt;span class="lnt"&gt;4
&lt;/span&gt;&lt;span class="lnt"&gt;5
&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;
&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-json" data-lang="json"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="err"&gt;lean&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="nt"&gt;&amp;#34;probable_root_cause&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;router state handoff regression&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;&lt;span class="nt"&gt;&amp;#34;next_file_to_read&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;router_notes.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="err"&gt;bloated&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="nt"&gt;&amp;#34;probable_root_cause&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;router state handoff regression&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;&lt;span class="nt"&gt;&amp;#34;next_file_to_read&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;router_notes.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;That result is useful. A stronger model such as Gemini can sometimes work through worse context, but that does not make the worse context harmless.&lt;/p&gt;
&lt;p&gt;The bloated profile still costs more, still gives the model more plausible ways to go wrong, and still makes the host pay for more ambiguity. The point is not to prove that a good model will always collapse under bad context. The practical goal is to set the system up for success: better odds of the right move, lower token cost, and fewer chances to drift.&lt;/p&gt;
&lt;p&gt;What to notice:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;The task is the same in both profiles. What changes is the planner&amp;rsquo;s situation.&lt;/li&gt;
&lt;li&gt;The lean profile gives the model two files, two clearly scoped tools, and one clean reference example.&lt;/li&gt;
&lt;li&gt;The bloated profile adds a stale checkout incident, a second example that points toward the wrong failure mode, and broader tools that make search look attractive.&lt;/li&gt;
&lt;li&gt;That is the real difference between helpful context and misleading context. The second profile is not just longer. It is more ambiguous.&lt;/li&gt;
&lt;li&gt;Even toy tool descriptions cost tokens. The schema for each tool costs more.&lt;/li&gt;
&lt;li&gt;In this entry, the tools are still just part of the input. The script is not executing &lt;code&gt;read_file&lt;/code&gt; or &lt;code&gt;search_repo&lt;/code&gt;; it is showing what the model would see.&lt;/li&gt;
&lt;li&gt;OpenRouter drifted on the bloated profile in the run above. Gemini did not. In this example, both observations point in the same direction: it helps to avoid making the planner solve a harder problem than necessary.&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;The behavioral consequence is the useful part. In the lean profile, a very plausible first move is &amp;ldquo;read the note about route replacement.&amp;rdquo; The debugging task already points to a narrow route/state-handoff problem, so broad search is a detour, not a good first move. In the bloated profile, &lt;code&gt;search_repo&lt;/code&gt; and the old migration incident can start looking reasonable even though they are worse bets.&lt;/p&gt;
&lt;h2 id="how-i-would-test-this"&gt;How I would test this
&lt;/h2&gt;&lt;p&gt;I would run the same task against both profiles several times and compare:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;whether the lean profile identifies route replacement or state handoff and names &lt;code&gt;router_notes.txt&lt;/code&gt; first&lt;/li&gt;
&lt;li&gt;whether the bloated profile drifts toward &lt;code&gt;migration_incident_2024.txt&lt;/code&gt;, provider-key explanations, or generic search&lt;/li&gt;
&lt;li&gt;how long and how generic the answer becomes&lt;/li&gt;
&lt;li&gt;how much prompt size grew relative to the extra useful signal&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;If I were wiring this into a real loop, I would also compare first-tool choice and later trace length. The point is to test whether extra context improved the planner&amp;rsquo;s situation or just made it busier.&lt;/p&gt;
&lt;h2 id="one-thing-to-change"&gt;One thing to change
&lt;/h2&gt;&lt;p&gt;Remove the clean reference example from the lean profile.&lt;/p&gt;
&lt;p&gt;Then run the same task again and see whether the answer gets less structured or the next file becomes less stable. That is a cheap way to feel the difference between:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;context that shows the output contract clearly&lt;/li&gt;
&lt;li&gt;context that only describes the task and hopes for the best&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;You can also add another stale migration note to the bloated profile and watch how quickly &amp;ldquo;helpful background&amp;rdquo; becomes an attractive distraction.&lt;/p&gt;
&lt;h2 id="what-breaks-first-in-practice"&gt;What breaks first in practice
&lt;/h2&gt;&lt;h3 id="1-too-much-context"&gt;1. Too much context
&lt;/h3&gt;&lt;p&gt;This is the dilution problem.&lt;/p&gt;
&lt;p&gt;Large tool sets, long examples, full repo dumps, and noisy logs all compete for the same window. Even harmless extras steal attention and budget. Anthropic&amp;rsquo;s September 29, 2025 article makes this point directly: context is finite, and the real job is curating the smallest useful set of tokens.&lt;/p&gt;
&lt;h3 id="2-wrong-context"&gt;2. Wrong context
&lt;/h3&gt;&lt;p&gt;Wrong context is about misdirection.&lt;/p&gt;
&lt;p&gt;The model can fail because the right file was absent, because a stale incident note looked plausible, because the wrong example dominated the pattern, or because broad tool descriptions pushed it toward the wrong action. From the outside, that can look like a reasoning failure, even when the problem started earlier in the assembled context.&lt;/p&gt;
&lt;h3 id="3-untrusted-context"&gt;3. Untrusted context
&lt;/h3&gt;&lt;p&gt;Any file, webpage, pasted log, or tool output you inject into the run becomes part of the planner&amp;rsquo;s situation.&lt;/p&gt;
&lt;p&gt;That matters even before the full safety post. If the source is noisy, hostile, stale, or misleading, then the planner is being asked to reason on top of shaky input. A more useful response is to treat context ingestion like a boundary worth designing, not just something to throw into the run.&lt;/p&gt;
&lt;h3 id="4-confusing-memory-with-current-context"&gt;4. Confusing memory with current context
&lt;/h3&gt;&lt;p&gt;If every old result, every note, and every trace gets stuffed back into the current run, then memory stops helping and starts polluting.&lt;/p&gt;
&lt;p&gt;This is one reason I like &lt;a class="link" href="https://docs.openclaw.ai/concepts/context" target="_blank" rel="noopener"
&gt;OpenClaw&amp;rsquo;s explicit separation between context and memory&lt;/a&gt;. It forces the question that should have been asked earlier: why is this in the current window at all?&lt;/p&gt;
&lt;h2 id="limits-of-this-entry"&gt;Limits of this entry
&lt;/h2&gt;&lt;p&gt;This post did not try to teach retrieval systems, RAG ranking, long-horizon memory, or context compaction in depth.&lt;/p&gt;
&lt;p&gt;It also stayed on static context assembly on purpose. In real agentic systems, context changes across steps, tool calls, and retries, and that dynamic management deserves its own treatment later in the series.&lt;/p&gt;
&lt;p&gt;The first task here was narrower: make context bigger than &amp;ldquo;the prompt,&amp;rdquo; show that context assembly is an engineering decision, and make the testing question explicit.&lt;/p&gt;
&lt;p&gt;A separate question, which I will leave for another post, is when the developer should own the next step instead of the model.&lt;/p&gt;
&lt;h2 id="posts-published-in-this-series"&gt;Posts published in this series
&lt;/h2&gt;&lt;ul&gt;
&lt;li&gt;&lt;a class="link" href="https://peterfulop.tech/p/agents-in-plain-english-for-developers/" target="_blank" rel="noopener"
&gt;Agents in plain English for developers&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a class="link" href="https://peterfulop.tech/p/in-agent-systems-context-matters-more-than-the-prompt/" target="_blank" rel="noopener"
&gt;In agent systems, context matters more than the prompt&lt;/a&gt;&lt;/li&gt;
&lt;/ul&gt;</description></item><item><title>Agents in plain English for developers</title><link>https://peterfulop.tech/p/agents-in-plain-english-for-developers/</link><pubDate>Fri, 03 Apr 2026 00:00:00 +0000</pubDate><guid>https://peterfulop.tech/p/agents-in-plain-english-for-developers/</guid><description>&lt;img src="https://peterfulop.tech/p/agents-in-plain-english-for-developers/agents-in-plain-english-for-developers.png" alt="Featured image of post Agents in plain English for developers" /&gt;&lt;p&gt;This is the first post in a series called &amp;ldquo;Agent systems in plain English&amp;rdquo; where I try to explain the concept of agents in a way that is easy to understand for developers.&lt;/p&gt;
&lt;p&gt;The word agent is now being used for too many different things.&lt;/p&gt;
&lt;p&gt;The term now covers everything from fixed workflows with a single LLM step to tool-using chatbots, browser-driving systems like &lt;a class="link" href="https://openai.com/index/computer-using-agent/" target="_blank" rel="noopener"
&gt;OpenAI&amp;rsquo;s Computer-Using Agent&lt;/a&gt;, and open agent stacks like &lt;a class="link" href="https://docs.openclaw.ai/" target="_blank" rel="noopener"
&gt;OpenClaw&lt;/a&gt;, &lt;a class="link" href="https://nanoclaw.dev/" target="_blank" rel="noopener"
&gt;NanoClaw&lt;/a&gt;, and &lt;a class="link" href="https://www.nvidia.com/en-us/ai/nemoclaw/" target="_blank" rel="noopener"
&gt;NemoClaw&lt;/a&gt;.
If the category feels muddy, this is why.&lt;/p&gt;
&lt;p&gt;This post is for developers who see the term everywhere and want a version they can implement in under 50 lines. The goal is not to settle a philosophy question. The goal is to make the idea concrete.&lt;/p&gt;
&lt;blockquote&gt;
&lt;p&gt;Most useful agentic systems reduce to context, tools, a host loop, and a runtime.&lt;/p&gt;
&lt;/blockquote&gt;
&lt;p&gt;If that sounds smaller than the marketing, good. Smaller is easier to reason about.&lt;/p&gt;
&lt;h2 id="who-owns-the-control-flow"&gt;Who owns the control flow?
&lt;/h2&gt;&lt;p&gt;That earlier definition gives us a simple starting point. The first useful question is who owns the control flow.&lt;/p&gt;
&lt;p&gt;By control flow, I mean who gets to decide the next step.&lt;/p&gt;
&lt;p&gt;In a workflow, the developer owns the control flow. In an agentic system, the model gets to choose at least some next steps inside a bounded runtime.&lt;/p&gt;
&lt;p&gt;A simple comparison makes this concrete. The difference shows up in who drives the loop, which tools are available, and how the runtime constrains the system.&lt;/p&gt;
&lt;p&gt;A workflow:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;fetch document&lt;/li&gt;
&lt;li&gt;summarize document&lt;/li&gt;
&lt;li&gt;classify summary&lt;/li&gt;
&lt;li&gt;send result&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;An agentic loop:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;ask the model to choose among &lt;code&gt;search&lt;/code&gt;, &lt;code&gt;read&lt;/code&gt;, &lt;code&gt;retry&lt;/code&gt;, &lt;code&gt;finish&lt;/code&gt;&lt;/li&gt;
&lt;li&gt;execute the allowed action&lt;/li&gt;
&lt;li&gt;feed the result back&lt;/li&gt;
&lt;li&gt;repeat until &lt;code&gt;finish&lt;/code&gt; or a runtime limit stops the loop&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;The important difference is not whether an LLM appears somewhere in the diagram. It is who gets to decide the next step.&lt;/p&gt;
&lt;p&gt;That is why not every LLM application is an agent. Many useful systems are better described as workflows, and in production that is often the better choice.&lt;/p&gt;
&lt;h2 id="the-smallest-useful-architecture"&gt;The smallest useful architecture
&lt;/h2&gt;&lt;p&gt;By itself, an LLM is not an agent. It predicts the next piece of text (a token) from the input it has been given (its context).&lt;/p&gt;
&lt;p&gt;It becomes agentic when you wrap four things around it:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;&lt;strong&gt;context&lt;/strong&gt;: the task, rules, examples, recent history, and local state the model gets to see&lt;/li&gt;
&lt;li&gt;&lt;strong&gt;tools&lt;/strong&gt;: structured ways to ask the outside world to do deterministic work, such as reading data, running a query, or fetching a page&lt;/li&gt;
&lt;li&gt;&lt;strong&gt;a host loop&lt;/strong&gt;: control flow that asks the model for the next step, executes allowed tool calls, feeds results back, and decides when to stop&lt;/li&gt;
&lt;li&gt;&lt;strong&gt;a runtime&lt;/strong&gt;: the system that enforces limits such as paths, timeouts, retries, network access, and confirmation gates&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;That gives you the smallest useful architecture:&lt;/p&gt;
&lt;p&gt;&lt;img src="https://peterfulop.tech/p/agents-in-plain-english-for-developers/the_smallest_architecture.png"
width="2556"
height="946"
srcset="https://peterfulop.tech/p/agents-in-plain-english-for-developers/the_smallest_architecture_hu_cc5f02680d2d069.png 480w, https://peterfulop.tech/p/agents-in-plain-english-for-developers/the_smallest_architecture_hu_efd54a7b53e3c206.png 1024w"
loading="lazy"
alt="The smallest useful architecture"
class="gallery-image"
data-flex-grow="270"
data-flex-basis="648px"
&gt;&lt;/p&gt;
&lt;p&gt;The short version is even simpler:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;the model proposes&lt;/li&gt;
&lt;li&gt;the host executes&lt;/li&gt;
&lt;li&gt;the runtime limits what can happen&lt;/li&gt;
&lt;/ul&gt;
&lt;h2 id="a-minimal-setup-for-running-the-examples"&gt;A minimal setup for running the examples
&lt;/h2&gt;&lt;p&gt;The examples in this post move in three steps: two tiny model probes that are useful but not agentic, and one tiny local agent loop that shows the agent shape directly.&lt;/p&gt;
&lt;p&gt;I created a &lt;a class="link" href="https://github.com/ipeterfulop/agent-systems-in-plain-english" target="_blank" rel="noopener"
&gt;dedicated GitHub repository&lt;/a&gt; for this series, but since the scripts are short, you will also find them included in this article.&lt;/p&gt;
&lt;p&gt;Also my intention is that the examples in this series are staying close to one-command runnable.
For these examples, I use &lt;a class="link" href="https://docs.astral.sh/uv/" target="_blank" rel="noopener"
&gt;Astral uv&lt;/a&gt; as the Python package and execution tool, and &lt;a class="link" href="https://peps.python.org/pep-0723/" target="_blank" rel="noopener"
&gt;PEP 723&lt;/a&gt; to declare script metadata inline.&lt;/p&gt;
&lt;p&gt;Install &lt;code&gt;uv&lt;/code&gt; once. On macOS and Linux:&lt;/p&gt;
&lt;div class="highlight"&gt;&lt;div class="chroma"&gt;
&lt;table class="lntable"&gt;&lt;tr&gt;&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code&gt;&lt;span class="lnt"&gt;1
&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;
&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-bash" data-lang="bash"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;curl -LsSf https://astral.sh/uv/install.sh &lt;span class="p"&gt;|&lt;/span&gt; sh
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;For Windows, use the &lt;a class="link" href="https://docs.astral.sh/uv/getting-started/installation/" target="_blank" rel="noopener"
&gt;official installation instructions&lt;/a&gt;. With &lt;a class="link" href="https://peps.python.org/pep-0723/" target="_blank" rel="noopener"
&gt;PEP 723&lt;/a&gt;, a Python file can carry its own inline metadata:&lt;/p&gt;
&lt;div class="highlight"&gt;&lt;div class="chroma"&gt;
&lt;table class="lntable"&gt;&lt;tr&gt;&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code&gt;&lt;span class="lnt"&gt;1
&lt;/span&gt;&lt;span class="lnt"&gt;2
&lt;/span&gt;&lt;span class="lnt"&gt;3
&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;
&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-python" data-lang="python"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# /// script&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# requires-python = &amp;#34;&amp;gt;=3.11&amp;#34;&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# ///&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;If the file needs third-party packages, the same block can also declare &lt;code&gt;dependencies = [...]&lt;/code&gt;, so &lt;code&gt;uv run script.py&lt;/code&gt; can build the environment and run the file in one step.&lt;/p&gt;
&lt;p&gt;Learning agents also does not require paying to get started. For this article, two routes are enough:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;default route: &lt;a class="link" href="https://openrouter.ai/collections/free-models" target="_blank" rel="noopener"
&gt;OpenRouter free models&lt;/a&gt;, especially &lt;a class="link" href="https://openrouter.ai/openrouter/free/" target="_blank" rel="noopener"
&gt;&lt;code&gt;openrouter/free&lt;/code&gt;&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;alternative route: &lt;a class="link" href="https://ai.google.dev/gemini-api/docs/api-key" target="_blank" rel="noopener"
&gt;Gemini API via Google AI Studio&lt;/a&gt;&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;Remarks:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;&lt;a class="link" href="https://openrouter.ai/pricing" target="_blank" rel="noopener"
&gt;OpenRouter&amp;rsquo;s pricing page&lt;/a&gt; says, as of March 28, 2026, that free users get 50 requests per day at 20 RPM, while pay-as-you-go accounts with at least 10 USD in credits get 1000 daily requests on free models at the same 20 RPM. Their docs also note that failed attempts still count.&lt;/li&gt;
&lt;li&gt;&lt;a class="link" href="https://ai.google.dev/gemini-api/docs/pricing" target="_blank" rel="noopener"
&gt;Google&amp;rsquo;s Gemini pricing page&lt;/a&gt; currently shows free-of-charge rows for preview models such as &lt;code&gt;gemini-3-flash-preview&lt;/code&gt; and &lt;code&gt;gemini-3.1-flash-lite-preview&lt;/code&gt;, while warning that preview models may change before becoming stable and may have different rate limits.&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;These are enough for this post: the goal is cheap experimentation, not production guarantees.&lt;/p&gt;
&lt;h2 id="baseline-one-model-call-that-is-not-an-agent"&gt;Baseline: one model call that is not an agent
&lt;/h2&gt;&lt;p&gt;Start with the plain request-response case. It is useful, but it is not agentic.&lt;/p&gt;
&lt;p&gt;If you want the commands exactly as written, call this file &lt;code&gt;free_probe.py&lt;/code&gt;:&lt;/p&gt;
&lt;div class="highlight"&gt;&lt;div class="chroma"&gt;
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&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-python" data-lang="python"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="ch"&gt;#!/usr/bin/env python3&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# /// script&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# requires-python = &amp;#34;&amp;gt;=3.11&amp;#34;&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# ///&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="kn"&gt;from&lt;/span&gt; &lt;span class="nn"&gt;__future__&lt;/span&gt; &lt;span class="kn"&gt;import&lt;/span&gt; &lt;span class="n"&gt;annotations&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="kn"&gt;import&lt;/span&gt; &lt;span class="nn"&gt;json&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="kn"&gt;import&lt;/span&gt; &lt;span class="nn"&gt;os&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="kn"&gt;from&lt;/span&gt; &lt;span class="nn"&gt;urllib&lt;/span&gt; &lt;span class="kn"&gt;import&lt;/span&gt; &lt;span class="n"&gt;request&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="n"&gt;payload&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;model&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;openrouter/free&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;messages&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;role&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;user&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;content&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;In one sentence, what is an agent loop?&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;}],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="n"&gt;req&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;request&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;Request&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;https://openrouter.ai/api/v1/chat/completions&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;data&lt;/span&gt;&lt;span class="o"&gt;=&lt;/span&gt;&lt;span class="n"&gt;json&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;dumps&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;payload&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;encode&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;utf-8&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;),&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;headers&lt;/span&gt;&lt;span class="o"&gt;=&lt;/span&gt;&lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;Authorization&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="sa"&gt;f&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;Bearer &lt;/span&gt;&lt;span class="si"&gt;{&lt;/span&gt;&lt;span class="n"&gt;os&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;environ&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s1"&gt;&amp;#39;OPENROUTER_API_KEY&amp;#39;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;&lt;span class="si"&gt;}&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;Content-Type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;application/json&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;},&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;)&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="k"&gt;with&lt;/span&gt; &lt;span class="n"&gt;request&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;urlopen&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;req&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;timeout&lt;/span&gt;&lt;span class="o"&gt;=&lt;/span&gt;&lt;span class="mi"&gt;60&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt; &lt;span class="k"&gt;as&lt;/span&gt; &lt;span class="n"&gt;response&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;body&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;json&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;loads&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;response&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;read&lt;/span&gt;&lt;span class="p"&gt;()&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;decode&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;utf-8&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;))&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="nb"&gt;print&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;body&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;choices&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="mi"&gt;0&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;message&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;content&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;strip&lt;/span&gt;&lt;span class="p"&gt;())&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;To run it, export your OpenRouter API key as an environment variable, then run the script with uv.&lt;/p&gt;
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&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-bash" data-lang="bash"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="nb"&gt;export&lt;/span&gt; &lt;span class="nv"&gt;OPENROUTER_API_KEY&lt;/span&gt;&lt;span class="o"&gt;=&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;...&amp;#34;&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;uv run free_probe.py
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;That is the boring baseline, and it is useful to see it plainly:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;there is no tool use&lt;/li&gt;
&lt;li&gt;there is no loop&lt;/li&gt;
&lt;li&gt;the model does not choose the next step&lt;/li&gt;
&lt;li&gt;the host makes one request and gets one answer&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;If you prefer Gemini, the same shape works there too. The endpoint, auth, and model name change. The architectural lesson does not.&lt;/p&gt;
&lt;h2 id="a-tiny-notes-agent"&gt;A tiny notes agent
&lt;/h2&gt;&lt;p&gt;If you want the commands exactly as written, call this file &lt;code&gt;notes_agent.py&lt;/code&gt;:&lt;/p&gt;
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&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-python" data-lang="python"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="ch"&gt;#!/usr/bin/env python3&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# /// script&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# requires-python = &amp;#34;&amp;gt;=3.11&amp;#34;&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="c1"&gt;# ///&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="n"&gt;NOTES&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;runtime.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;A runtime enforces limits such as paths, timeouts, and permissions.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;quotas.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;Free API access usually comes with quotas such as daily request caps and rate limits.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;agents.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;An agentic system lets the model choose some next steps inside a bounded loop.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="n"&gt;TOOLS&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;search_notes&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="k"&gt;lambda&lt;/span&gt; &lt;span class="n"&gt;query&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;name&lt;/span&gt; &lt;span class="k"&gt;for&lt;/span&gt; &lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;text&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;NOTES&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;items&lt;/span&gt;&lt;span class="p"&gt;()&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;query&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;lower&lt;/span&gt;&lt;span class="p"&gt;()&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;lower&lt;/span&gt;&lt;span class="p"&gt;()&lt;/span&gt; &lt;span class="ow"&gt;or&lt;/span&gt; &lt;span class="n"&gt;query&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;lower&lt;/span&gt;&lt;span class="p"&gt;()&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;text&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;lower&lt;/span&gt;&lt;span class="p"&gt;()&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="s2"&gt;&amp;#34;read_note&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="k"&gt;lambda&lt;/span&gt; &lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;NOTES&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="k"&gt;def&lt;/span&gt; &lt;span class="nf"&gt;planner&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;task&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;trace&lt;/span&gt;&lt;span class="p"&gt;):&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;task_l&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;task&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;lower&lt;/span&gt;&lt;span class="p"&gt;()&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;need_runtime&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;runtime&amp;#34;&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;task_l&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;need_quota&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;quota&amp;#34;&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;task_l&lt;/span&gt; &lt;span class="ow"&gt;or&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;rate limit&amp;#34;&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;task_l&lt;/span&gt; &lt;span class="ow"&gt;or&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;cap&amp;#34;&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;task_l&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="ow"&gt;not&lt;/span&gt; &lt;span class="n"&gt;trace&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;query&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;limit&amp;#34;&lt;/span&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;need_runtime&lt;/span&gt; &lt;span class="ow"&gt;and&lt;/span&gt; &lt;span class="n"&gt;need_quota&lt;/span&gt; &lt;span class="k"&gt;else&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;runtime&amp;#34;&lt;/span&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;need_runtime&lt;/span&gt; &lt;span class="k"&gt;else&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;quota&amp;#34;&lt;/span&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;need_quota&lt;/span&gt; &lt;span class="k"&gt;else&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;agent&amp;#34;&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;search_notes&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;args&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;query&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;query&lt;/span&gt;&lt;span class="p"&gt;}}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;last&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;trace&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="o"&gt;-&lt;/span&gt;&lt;span class="mi"&gt;1&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;last&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;action&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt; &lt;span class="o"&gt;==&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;search_notes&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;matches&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;last&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;result&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="ow"&gt;not&lt;/span&gt; &lt;span class="n"&gt;matches&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;finish&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;answer&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;No relevant note found.&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;read_note&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;args&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;name&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;matches&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="mi"&gt;0&lt;/span&gt;&lt;span class="p"&gt;]}}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;last&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;action&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt; &lt;span class="o"&gt;==&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;read_note&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;read_names&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="n"&gt;step&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;action&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;args&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;name&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt; &lt;span class="k"&gt;for&lt;/span&gt; &lt;span class="n"&gt;step&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;trace&lt;/span&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;step&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;action&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;][&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt; &lt;span class="o"&gt;==&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;read_note&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;need_runtime&lt;/span&gt; &lt;span class="ow"&gt;and&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;runtime.txt&amp;#34;&lt;/span&gt; &lt;span class="ow"&gt;not&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;read_names&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;read_note&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;args&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;name&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;runtime.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;}}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;need_quota&lt;/span&gt; &lt;span class="ow"&gt;and&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;quotas.txt&amp;#34;&lt;/span&gt; &lt;span class="ow"&gt;not&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;read_names&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;read_note&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;args&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;name&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;quotas.txt&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;}}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;parts&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="n"&gt;NOTES&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="n"&gt;name&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt; &lt;span class="k"&gt;for&lt;/span&gt; &lt;span class="n"&gt;name&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;read_names&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;finish&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;answer&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34; &amp;#34;&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;join&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;parts&lt;/span&gt;&lt;span class="p"&gt;)}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;finish&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;answer&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;I do not know&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="k"&gt;def&lt;/span&gt; &lt;span class="nf"&gt;run_agent&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;task&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;max_steps&lt;/span&gt;&lt;span class="o"&gt;=&lt;/span&gt;&lt;span class="mi"&gt;5&lt;/span&gt;&lt;span class="p"&gt;):&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;trace&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="p"&gt;[]&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;for&lt;/span&gt; &lt;span class="n"&gt;step&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="nb"&gt;range&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;max_steps&lt;/span&gt;&lt;span class="p"&gt;):&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;action&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;planner&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;task&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="n"&gt;trace&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;action&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt; &lt;span class="o"&gt;==&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;finish&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;answer&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;action&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;answer&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;],&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;trace&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;trace&lt;/span&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;if&lt;/span&gt; &lt;span class="n"&gt;action&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;type&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt; &lt;span class="o"&gt;!=&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt; &lt;span class="ow"&gt;or&lt;/span&gt; &lt;span class="n"&gt;action&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]&lt;/span&gt; &lt;span class="ow"&gt;not&lt;/span&gt; &lt;span class="ow"&gt;in&lt;/span&gt; &lt;span class="n"&gt;TOOLS&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;error&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;invalid action&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;trace&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;trace&lt;/span&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;result&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="n"&gt;TOOLS&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="n"&gt;action&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;tool&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;]](&lt;/span&gt;&lt;span class="o"&gt;**&lt;/span&gt;&lt;span class="n"&gt;action&lt;/span&gt;&lt;span class="p"&gt;[&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;args&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;])&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="n"&gt;trace&lt;/span&gt;&lt;span class="o"&gt;.&lt;/span&gt;&lt;span class="n"&gt;append&lt;/span&gt;&lt;span class="p"&gt;({&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;step&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;step&lt;/span&gt; &lt;span class="o"&gt;+&lt;/span&gt; &lt;span class="mi"&gt;1&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;action&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;action&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;result&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;result&lt;/span&gt;&lt;span class="p"&gt;})&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt; &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;error&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;max_steps reached&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;,&lt;/span&gt; &lt;span class="s2"&gt;&amp;#34;trace&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="n"&gt;trace&lt;/span&gt;&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;
&lt;/span&gt;&lt;/span&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;&lt;span class="nb"&gt;print&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="n"&gt;run_agent&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="s2"&gt;&amp;#34;What limits does the runtime enforce, and what quotas apply to free API access?&amp;#34;&lt;/span&gt;&lt;span class="p"&gt;))&lt;/span&gt;
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;Run it:&lt;/p&gt;
&lt;div class="highlight"&gt;&lt;div class="chroma"&gt;
&lt;table class="lntable"&gt;&lt;tr&gt;&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code&gt;&lt;span class="lnt"&gt;1
&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;
&lt;td class="lntd"&gt;
&lt;pre tabindex="0" class="chroma"&gt;&lt;code class="language-bash" data-lang="bash"&gt;&lt;span class="line"&gt;&lt;span class="cl"&gt;uv run notes_agent.py
&lt;/span&gt;&lt;/span&gt;&lt;/code&gt;&lt;/pre&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;/div&gt;
&lt;/div&gt;&lt;p&gt;This is still a teaching example, not a general agent.&lt;br&gt;
That is deliberate. The first tool call does not answer the question, so the planner has to search, inspect the result, read one note, and then read another before it can finish.&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;&lt;code&gt;TOOLS&lt;/code&gt; defines what the system is allowed to do. If an action is not in that dictionary, it cannot happen.&lt;/li&gt;
&lt;li&gt;&lt;code&gt;trace&lt;/code&gt; is the running state. In this teaching example, the planner uses it to see what has already been read and what still needs to happen.&lt;/li&gt;
&lt;li&gt;&lt;code&gt;planner(...)&lt;/code&gt; chooses the next action. In this teaching example it is deterministic. In a real agent, this is the part that becomes an LLM call returning structured output.&lt;/li&gt;
&lt;li&gt;&lt;code&gt;run_agent(...)&lt;/code&gt; is still in charge. The host asks for the next action, validates it, executes it, records the result, and decides when the run ends.&lt;/li&gt;
&lt;li&gt;&lt;code&gt;max_steps&lt;/code&gt; is already runtime policy. It is small and boring, which is exactly why it matters.&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;When people say &amp;ldquo;an LLM is an agent,&amp;rdquo; the useful engineering interpretation is narrower than that. The model is being used as the planner inside a larger mechanism.&lt;/p&gt;
&lt;p&gt;If you replace &lt;code&gt;planner(...)&lt;/code&gt; with a real LLM call, the shape stays the same. What changes is the source of uncertainty:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;next-step choice becomes probabilistic&lt;/li&gt;
&lt;li&gt;tool selection becomes a matter of model judgment&lt;/li&gt;
&lt;li&gt;tool outputs have to be fed back into context&lt;/li&gt;
&lt;li&gt;stopping rules matter more&lt;/li&gt;
&lt;li&gt;noisy traces start to degrade later decisions&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;Swapping in an LLM changes the planner, not the surrounding machinery.&lt;/p&gt;
&lt;h2 id="the-same-loop-can-become-dangerous-very-quickly"&gt;The same loop can become dangerous very quickly
&lt;/h2&gt;&lt;p&gt;The teaching example above is harmless because the tool surface is tiny, the loop is bounded, and nothing touches the filesystem or the network.&lt;/p&gt;
&lt;p&gt;Now replace &lt;code&gt;read_note(name)&lt;/code&gt; with &lt;code&gt;delete_file(path)&lt;/code&gt; and remove path restrictions.&lt;/p&gt;
&lt;p&gt;The planner did not become smarter. The loop did not become more advanced. What changed is the blast radius. The runtime is now less restrictive.&lt;/p&gt;
&lt;p&gt;That is why the practical questions are not mystical ones. They are plain engineering questions:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;which tools exist?&lt;/li&gt;
&lt;li&gt;which arguments are allowed?&lt;/li&gt;
&lt;li&gt;which paths are writable?&lt;/li&gt;
&lt;li&gt;which actions need confirmation?&lt;/li&gt;
&lt;li&gt;what stops the loop?&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;The exact same planner can be safe, annoying, or dangerous depending on those answers.&lt;/p&gt;
&lt;h2 id="what-breaks-first-in-practice"&gt;What breaks first in practice
&lt;/h2&gt;&lt;p&gt;Once the basic shape is visible, three caveats matter immediately.&lt;/p&gt;
&lt;h3 id="1-reliability-fails-before-the-demo-stops-looking-impressive"&gt;1. Reliability fails before the demo stops looking impressive
&lt;/h3&gt;&lt;p&gt;The first successful run creates false confidence.&lt;/p&gt;
&lt;p&gt;A small agent loop often works once or twice before it shows what is missing:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;tool descriptions were ambiguous&lt;/li&gt;
&lt;li&gt;tool outputs were too noisy&lt;/li&gt;
&lt;li&gt;the trace kept the wrong details&lt;/li&gt;
&lt;li&gt;the stopping rule was too weak&lt;/li&gt;
&lt;li&gt;the model kept retrying a bad idea&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;These are engineering problems. That is good news. They can be studied and improved, but they do not disappear just because the first demo looked smooth.&lt;/p&gt;
&lt;h3 id="2-permissions-define-the-blast-radius"&gt;2. Permissions define the blast radius
&lt;/h3&gt;&lt;p&gt;As soon as the runtime can touch shell commands, files, browsers, inboxes, or APIs, the question changes.&lt;/p&gt;
&lt;p&gt;It is no longer &amp;ldquo;is the prompt good?&amp;rdquo;&lt;/p&gt;
&lt;p&gt;It is &amp;ldquo;what is this system allowed to damage?&amp;rdquo;&lt;/p&gt;
&lt;p&gt;That is one reason the current open stacks are worth studying. For example, &lt;a class="link" href="https://www.nvidia.com/en-us/ai/nemoclaw/" target="_blank" rel="noopener"
&gt;NVIDIA&amp;rsquo;s NemoClaw page&lt;/a&gt; explicitly positions it as OpenClaw with added security and privacy controls. Systems like &lt;a class="link" href="https://docs.openclaw.ai/" target="_blank" rel="noopener"
&gt;OpenClaw&lt;/a&gt;, &lt;a class="link" href="https://nanoclaw.dev/" target="_blank" rel="noopener"
&gt;NanoClaw&lt;/a&gt;, and &lt;a class="link" href="https://www.nvidia.com/en-us/ai/nemoclaw/" target="_blank" rel="noopener"
&gt;NemoClaw&lt;/a&gt; are interesting not because they finally discovered magic, but because they make context assembly, tool surfaces, and runtime policy impossible to ignore.&lt;/p&gt;
&lt;h3 id="3-free-tiers-are-excellent-for-learning-and-bad-as-a-promise"&gt;3. Free tiers are excellent for learning and bad as a promise
&lt;/h3&gt;&lt;p&gt;Free access is enough to study the mechanics. It is not a stable production contract.&lt;/p&gt;
&lt;p&gt;Provider pages such as &lt;a class="link" href="https://openrouter.ai/pricing" target="_blank" rel="noopener"
&gt;OpenRouter pricing&lt;/a&gt; and &lt;a class="link" href="https://ai.google.dev/gemini-api/docs/pricing" target="_blank" rel="noopener"
&gt;Gemini pricing&lt;/a&gt; tell the same story in slightly different language: quotas, previews, and temporary unavailability are part of the deal.&lt;/p&gt;
&lt;p&gt;That is fine. You can still learn a great deal without paying. Just do not confuse &amp;ldquo;free enough to experiment&amp;rdquo; with &amp;ldquo;stable enough to promise.&amp;rdquo;&lt;/p&gt;
&lt;h2 id="what-this-article-does-not-cover"&gt;What this article does not cover
&lt;/h2&gt;&lt;p&gt;These limits are deliberate. This article does not try to cover memory, &lt;a class="link" href="https://modelcontextprotocol.io/" target="_blank" rel="noopener"
&gt;Model Context Protocol&lt;/a&gt;, browser control, multi-agent delegation, long-running jobs, or evals.&lt;/p&gt;
&lt;p&gt;The goal of this post is narrower:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;tell workflows and agentic loops apart&lt;/li&gt;
&lt;li&gt;name the smallest useful architecture&lt;/li&gt;
&lt;li&gt;make the structure visible in one small file&lt;/li&gt;
&lt;li&gt;show why runtime policy matters immediately&lt;/li&gt;
&lt;/ul&gt;
&lt;p&gt;In the next post in this series, I will narrow the focus further and turn to the most underrated part of the whole stack: context engineering.&lt;/p&gt;
&lt;p&gt;Just as a teaser in the next article &amp;ldquo;Context engineering is the core job&amp;rdquo; I will cover topics as:&lt;/p&gt;
&lt;ul&gt;
&lt;li&gt;why context is larger than the prompt&lt;/li&gt;
&lt;li&gt;why bigger context is not automatically better context&lt;/li&gt;
&lt;li&gt;the difference between context and memory&lt;/li&gt;
&lt;li&gt;how context assembly changes model behavior&lt;/li&gt;
&lt;/ul&gt;
&lt;h2 id="posts-published-in-this-series"&gt;Posts published in this series
&lt;/h2&gt;&lt;ul&gt;
&lt;li&gt;&lt;a class="link" href="https://peterfulop.tech/p/agents-in-plain-english-for-developers/" target="_blank" rel="noopener"
&gt;Agents in plain English for developers&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;&lt;a class="link" href="https://peterfulop.tech/p/in-agent-systems-context-matters-more-than-the-prompt/" target="_blank" rel="noopener"
&gt;In agent systems, context matters more than the prompt&lt;/a&gt;&lt;/li&gt;
&lt;/ul&gt;</description></item></channel></rss>