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<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>GitHub Copilot Token Optimization - 8 Hour Workshop</title>
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</head>
<body>
<div class="reveal">
<div class="slides">
<section>
<p class="kicker">8 hour customer workshop</p>
<h1>GitHub Copilot Token Optimization</h1>
<p>Reduce token spend without losing quality. Set enterprise spending limits.</p>
<aside class="notes">
Open with disclaimer: community guide, not official GitHub or Microsoft guidance. Use official docs for supported controls.
</aside>
</section>
<section>
<h2>Workshop outcome</h2>
<div class="grid-3">
<div class="card">
<h3>Explain cost</h3>
<p>Input, output, cached tokens, agent loops, MCP schemas, model routing.</p>
</div>
<div class="card">
<h3>Change behavior</h3>
<p>Prompt compression, output control, context hygiene, Ask/Edit/Agent routing.</p>
</div>
<div class="card">
<h3>Build a rollout plan</h3>
<p>Enterprise budgets, model policy, instruction scope, monthly review loop.</p>
</div>
</div>
</section>
<section>
<h2>Important framing</h2>
<div class="quote">
This is a community guide, not official GitHub or Microsoft guidance.
</div>
<p class="small">Use <code>docs.github.com/copilot</code> for supported feature behavior, billing controls, and admin policy.</p>
</section>
<section>
<h2>8 hour agenda</h2>
<table>
<thead>
<tr><th>Time</th><th>Block</th><th>Output</th></tr>
</thead>
<tbody>
<tr><td>00:00-00:30</td><td>Why tokens matter + fast wins</td><td>Shared cost model</td></tr>
<tr><td>00:30-02:00</td><td>Prompt, language, output labs</td><td>Terse prompt templates</td></tr>
<tr><td>02:00-03:15</td><td>Context + always-on files</td><td>Instruction pruning diff</td></tr>
<tr><td>03:15-04:15</td><td>Workflow + modes</td><td>Mode routing cheat sheet</td></tr>
<tr><td>04:15-05:15</td><td>MCP/tool costs + data</td><td>MCP audit list</td></tr>
<tr><td>05:15-06:15</td><td>Practical setup</td><td>Repo setup checklist</td></tr>
<tr><td>06:15-07:10</td><td>Model/pricing + governance</td><td>Customer admin rollout</td></tr>
<tr><td>07:10-07:40</td><td>Outcome per token</td><td>Plan/execute/verify loop</td></tr>
<tr><td>07:40-08:00</td><td>Capstone</td><td>30 day token plan</td></tr>
</tbody>
</table>
</section>
<section>
<h2>Navigation</h2>
<p>Move horizontally between chapters. Move vertically through each chapter's slides and labs.</p>
<p class="small muted">Press <code>Esc</code> for overview. Press <code>S</code> for speaker notes.</p>
</section>
<section>
<section>
<p class="kicker">Quick Start</p>
<h2>14 things to do right now</h2>
<p>Cut unwanted output, reduce repeated context, then choose models and tools by task.</p>
</section>
<section>
<h2>Fastest wins</h2>
<ol>
<li><strong>Code-only responses</strong>: skip explanations when you need only code.</li>
<li><strong>Constrain format</strong>: bullets, one sentence, JSON, tables.</li>
<li><strong>Shrink always-on context</strong>: instructions and agent files.</li>
<li><strong>Use Auto by default</strong>: pin premium only when justified.</li>
<li><strong>Use Ask Mode</strong> for simple questions.</li>
</ol>
</section>
<section>
<h2>More fast wins</h2>
<ol start="6">
<li><strong>Scope context with <code>applyTo</code></strong>.</li>
<li><strong>Write precise prompts</strong>: target file, function, done condition.</li>
<li><strong>Retune prompts to target model</strong>.</li>
<li><strong>Audit MCP servers</strong>.</li>
<li><strong>Convert rich files to Markdown first</strong>.</li>
</ol>
</section>
<section>
<h2>More fast wins, continued</h2>
<ol start="11">
<li><strong>Run <code>/chronicle cost tips</code> & <code>/chronicle improve</code></strong> in Copilot CLI.</li>
<li><strong>Use AI Engineering Coach</strong> for VS Code habit review.</li>
<li><strong>Try CodeAct</strong> for long CLI tool chains.</li>
<li><strong>Build a Graphify map</strong> for repeated codebase navigation.</li>
</ol>
</section>
<section>
<h2>The priority stack</h2>
<div class="grid-3">
<div class="card">
<h3>Output first</h3>
<p>Set a concise response default.</p>
</div>
<div class="card">
<h3>Always-on second</h3>
<p>Remove context repeated on every turn.</p>
</div>
<div class="card">
<h3>Mode third</h3>
<p>Choose Ask, Edit, or Agent for the task.</p>
</div>
<div class="card">
<h3>Governance fourth</h3>
<p>Budgets and model policy cap spend.</p>
</div>
<div class="card">
<h3>Outcome fifth</h3>
<p>Plan, route, verify, close.</p>
</div>
</div>
</section>
<section>
<h2>Lab 0: baseline your habits</h2>
<div class="card lab">
<h3>Goal</h3>
<p>Identify your top 3 token leaks before learning techniques.</p>
<p><strong>Do:</strong> mark each as green/yellow/red: output verbosity, instruction size, open tabs, Agent use, MCP count, model pinning, long chat history.</p>
<p><strong>Deliverable:</strong> personal baseline + one "fix today" action.</p>
<p><strong>Time:</strong> 10 minutes.</p>
</div>
</section>
</section>
<section>
<section>
<p class="kicker">Part 1</p>
<h2>Why tokens matter</h2>
<p>Tokens drive cost, speed, limits, and context capacity.</p>
</section>
<section>
<h2>Tokens are subwords</h2>
<div class="two-col">
<div class="card">
<h3>BPE behavior</h3>
<ul>
<li>Common words can be one token.</li>
<li>Rare words split into pieces.</li>
<li>Punctuation and filler still count.</li>
</ul>
</div>
<div class="card">
<h3>Core insight</h3>
<p><code>Sure, I'd be happy to help!</code> uses around 10 tokens without answering the question.</p>
</div>
</div>
</section>
<section>
<h2>Cost model</h2>
<img class="diagram diagram-compact" src="../docs/assets/diagrams/token-cost-anatomy.svg" alt="Token cost anatomy: input tokens include hidden context, output tokens are the visible answer, cached tokens reuse stable prefix.">
<p class="small warning">Output tokens usually cost materially more than input tokens in vendor pricing examples.</p>
</section>
<section>
<h2>Input is bigger than your prompt</h2>
<pre><code class="language-text">Context window
├─ System prompt
├─ copilot-instructions.md / AGENTS.md
├─ File context and open tabs
├─ Conversation history
├─ MCP tool schemas
└─ Your typed prompt</code></pre>
<p class="small">A 20-word prompt can be sent with thousands of context tokens.</p>
</section>
<section>
<h2>Coding Agent multiplier</h2>
<p>One issue-to-PR run is not one request.</p>
<div class="grid">
<div class="card">
<h3>Agent steps</h3>
<p>Plan, search, read files, edit, run tests, inspect failures, retry.</p>
</div>
<div class="card">
<h3>Compounding</h3>
<p>Every step reloads baseline context and adds previous tool results.</p>
</div>
</div>
</section>
<section>
<h2>Lab 1: token anatomy</h2>
<div class="card lab">
<h3>Goal</h3>
<p>Separate visible prompt from hidden context.</p>
<p><strong>Do:</strong> choose one recent Copilot task. List likely context sources: open files, referenced files, instructions, history, tools, output.</p>
<p><strong>Discuss:</strong> which source was most controllable?</p>
<p><strong>Time:</strong> 15 minutes.</p>
</div>
</section>
</section>
<section>
<section>
<p class="kicker">Part 2.1</p>
<h2>Prompt compression</h2>
<p>Make the request clear before making it shorter. Keep technical terms and constraints exact.</p>
<p class="small">Ordinary concise language is the default. Shorthand is optional.</p>
</section>
<section>
<h2>Optional shorthand</h2>
<div class="grid">
<div class="card">
<h3>Drop</h3>
<p>Redundant wording and pleasantries that add no task information.</p>
</div>
<div class="card">
<h3>Keep</h3>
<p>Technical terms, code, filenames, negation, conditions, and acceptance checks.</p>
</div>
</div>
<p class="accent"><code>[thing] [action] [reason]. [next step].</code></p>
<p class="small">Keep full sentences when fragments hide who does what.</p>
</section>
<section>
<h2>Before vs after</h2>
<table>
<thead><tr><th>Wordy</th><th>Concise</th></tr></thead>
<tbody>
<tr>
<td>Could you please review this pull request and let me know if there are any issues?</td>
<td><code>Review PR. Flag issues.</code></td>
</tr>
<tr>
<td>Can you explain what this error message means and how I should fix it?</td>
<td><code>Explain this error and how to fix it.</code></td>
</tr>
</tbody>
</table>
</section>
<section>
<h2>Compression levels</h2>
<table>
<thead><tr><th>Level</th><th>Style</th><th>Use when</th></tr></thead>
<tbody>
<tr><td>Concise prose</td><td>Plain, complete wording</td><td>Default</td></tr>
<tr><td>Fragments</td><td>Shared terms, short clauses</td><td>Actors and conditions stay clear</td></tr>
<tr><td>Dense shorthand</td><td>Abbreviations, arrows</td><td>Only if readers can decode it reliably</td></tr>
</tbody>
</table>
</section>
<section>
<h2>Structured beats prose</h2>
<pre><code class="language-text">POST /api/users
Validate:
- name: string, required
- email: string, required, valid
400 on validation fail
201 on success, return created user
Save to DB</code></pre>
<p class="small">Bullets and key-value pairs force clarity and reduce filler.</p>
</section>
<section>
<h2>Code-centric prompting</h2>
<div class="grid">
<div class="card">
<h3>Natural language</h3>
<p>Create a function that takes numbers, filters negative values, doubles remaining values, returns sum.</p>
</div>
<div class="card">
<h3>Code-centric</h3>
<p><code>fn(nums) -> filter(>0) -> map(*2) -> sum</code></p>
<p><code>Like getUserById but for emails. 404 if missing.</code></p>
</div>
</div>
</section>
<section>
<h2>Guardrails as invariants</h2>
<table>
<thead><tr><th>Verbose procedure</th><th>Compressed invariant</th></tr></thead>
<tbody>
<tr><td>Make sure every SQL query parameterizes values...</td><td><code>SQL: parameterized queries only. No concatenation.</code></td></tr>
<tr><td>Please write tests for any new code...</td><td><code>New code -> tests. Cover happy + error.</code></td></tr>
</tbody>
</table>
</section>
<section>
<h2>Lab 2: prompt compression ladder</h2>
<div class="card lab">
<h3>Goal</h3>
<p>Rewrite one real prompt three ways: lite, full, ultra.</p>
<p><strong>Do:</strong> preserve file names, line numbers, constraints, done condition. Drop only fluff.</p>
<p><strong>Compare:</strong> which version is shortest without adding ambiguity?</p>
<p><strong>Time:</strong> 20 minutes.</p>
</div>
</section>
<section>
<h2>Lab 3: prompt A/B</h2>
<div class="card lab">
<h3>Try this vs that</h3>
<pre><code class="language-text">A: Could you take a look at auth and improve error handling?
B: File: src/auth/login.ts.
Bug: null user causes .email crash.
Fix: null guard before .email.
Test: add null-user case.
Done: targeted test passes.</code></pre>
<p><strong>Run:</strong> ask Copilot with A, then B. Compare file reads, clarifications, output length.</p>
</div>
</section>
</section>
<section>
<section>
<p class="kicker">Part 2.2</p>
<h2>Language comparison</h2>
<p>Compare token counts, not character counts.</p>
</section>
<section>
<h2>CJK assumption fails</h2>
<table>
<thead><tr><th>Language</th><th>Sentence</th><th>Tokens</th><th>vs English</th></tr></thead>
<tbody>
<tr><td>English</td><td>I met a huge dog</td><td>5</td><td>1.0x</td></tr>
<tr><td>Spanish</td><td>Conoci a un perro enorme</td><td>8</td><td>1.6x</td></tr>
<tr><td>Chinese</td><td>Chinese equivalent</td><td>11</td><td>2.2x</td></tr>
<tr><td>Japanese</td><td>Japanese equivalent</td><td>11</td><td>2.2x</td></tr>
<tr><td>Russian</td><td>Russian equivalent</td><td>14</td><td>2.8x</td></tr>
</tbody>
</table>
</section>
<section>
<h2>Why</h2>
<ul>
<li>BPE tokenizers are trained heavily on English.</li>
<li>Common English words often get one token.</li>
<li>CJK text has fewer characters, but more tokens per character.</li>
<li>Non-Latin scripts often cost more; transliteration can help.</li>
</ul>
</section>
<section>
<h2>Practical rule</h2>
<div class="quote">
Use terse English for prompts and instructions. Do not translate to CJK to save tokens.
</div>
<p class="small">If you express requirements more clearly in your native language, that clarity can outweigh the token savings.</p>
</section>
<section>
<h2>Lab 4: tokenizer reality check</h2>
<div class="card lab">
<h3>Goal</h3>
<p>Disprove or confirm language assumptions with actual token counts.</p>
<p><strong>Do:</strong> pick one prompt. Translate to your strongest non-English language. Compare token counts in tokenizer tool.</p>
<p><strong>Deliverable:</strong> team language guidance: when English is required, when native language is OK.</p>
<p><strong>Time:</strong> 20 minutes.</p>
</div>
</section>
</section>
<section>
<section>
<p class="kicker">Part 2.3</p>
<h2>Context management</h2>
<p>Control which files, instructions, and history get sent.</p>
</section>
<section>
<h2>Always-on files cost every turn</h2>
<p><code>.github/copilot-instructions.md</code>, <code>AGENTS.md</code>, <code>CLAUDE.md</code>, and similar files can become persistent context.</p>
<p class="small warning">Duplicate rules add context twice when both files are loaded.</p>
</section>
<section>
<h2>Prune before compressing</h2>
<p>Delete duplicate rules, stale notes, and facts visible in code. Keep project-specific pitfalls.</p>
<p class="small">The reusable response template lives in Practical Setup. No token-count estimate is needed to decide whether a rule is relevant.</p>
</section>
<section>
<h2>Context hygiene</h2>
<ul>
<li>Close files not relevant to current task.</li>
<li>Keep files focused and small.</li>
<li>Ignore build output, vendor dirs, generated files.</li>
<li>Use Content Exclusion for sensitive paths in Business/Enterprise.</li>
<li>Start fresh conversations after topic changes.</li>
</ul>
</section>
<section>
<h2>Use scoped instructions</h2>
<pre><code class="language-markdown">---
applyTo: "src/api/**/*.ts"
---
API conventions:
- Routes in src/api/routes/. Handlers thin, logic in services/.
- Validate with zod.
- Errors via Result<T,E>, never throw.</code></pre>
<p class="small">Load path-specific guidance only for matching files.</p>
</section>
<section>
<h2>Always-on vs conditional vs on-demand</h2>
<img class="diagram diagram-compact" src="../docs/assets/diagrams/context-loading-boundaries.svg" alt="Always-on context should be tiny; scoped instructions load by path; on-demand skills load when invoked.">
</section>
<section>
<h2>Normalize rich files first</h2>
<img class="diagram diagram-compact" src="../docs/assets/diagrams/format-tax-pipeline.svg" alt="Rich files carry format noise; MarkItDown converts them to clean Markdown before AI work.">
</section>
<section>
<h2>Cache-friendly behavior</h2>
<img class="diagram diagram-compact" src="../docs/assets/diagrams/cache-stability.svg" alt="Stable thread reuses prefix; cache-busted thread switches model, tools, or agent and should start fresh with a handoff.">
</section>
<section>
<h2>Persistent graph navigation</h2>
<img class="diagram diagram-compact" src="../docs/assets/diagrams/graphify-navigation.svg" alt="Graphify builds graph.json once so agents can query the map instead of rereading broad file sets.">
</section>
<section>
<h2>Enterprise note: Content Exclusion</h2>
<div class="card enterprise">
<h3>Customer-side action</h3>
<p>Configure Content Exclusion for sensitive files, generated bundles, large data files, and regulated paths.</p>
<p><strong>Important:</strong> treat this as privacy/policy control first, token-saving side effect second. Check current surface support in official docs.</p>
</div>
</section>
<section>
<h2>Lab 5: context audit</h2>
<div class="card lab">
<h3>Goal</h3>
<p>Find always-on context that should become scoped or on-demand.</p>
<p><strong>Do:</strong> inspect repo instructions, AGENTS/CLAUDE files, open tabs, generated files, MCP config.</p>
<p><strong>Deliverable:</strong> three-column list: keep always-on, move to <code>applyTo</code>, move on-demand/delete.</p>
<p><strong>Time:</strong> 30 minutes.</p>
</div>
</section>
</section>
<section>
<section>
<p class="kicker">Part 2.4</p>
<h2>Output control</h2>
<p>Ask for the answer format you need. Skip unwanted explanation.</p>
</section>
<section>
<h2>Task-specific code output</h2>
<pre><code class="language-text">Code only, no explanation.</code></pre>
<p>Best for generation tasks when team already understands desired change.</p>
</section>
<section>
<h2>Format constraints</h2>
<table>
<thead><tr><th>Instruction</th><th>Use when</th></tr></thead>
<tbody>
<tr><td>Answer in one sentence</td><td>Quick decision or explanation</td></tr>
<tr><td>3 bullets max</td><td>Scan-friendly summary</td></tr>
<tr><td>Reply as JSON</td><td>Machine-readable extraction</td></tr>
<tr><td>Yes/no, then one line why</td><td>Review gate</td></tr>
<tr><td>Diff only</td><td>Patch inspection</td></tr>
</tbody>
</table>
</section>
<section>
<h2>Project default</h2>
<p>Lead with the answer. Keep explanations proportional to the task, with verification evidence and blockers intact.</p>
<p class="small">Use the single <a href="../10-practical-setup/#step-1-set-a-concise-response-default">starter template</a>, then add relevant project rules.</p>
</section>
<section>
<h2>Lab 6: output A/B</h2>
<div class="card lab">
<h3>Try this vs that</h3>
<pre><code class="language-text">A: Add input validation to processOrder().
B: Add input validation to processOrder().
Code only. No explanation. Minimal diff.</code></pre>
<p><strong>Measure:</strong> acceptance checks, full token usage, billed cost, time, and retries, not only response length.</p>
<p><strong>Time:</strong> 15 minutes.</p>
</div>
</section>
<section>
<h2>Lab 7: format forcing</h2>
<div class="card lab">
<h3>Goal</h3>
<p>Practice asking for bounded output.</p>
<p><strong>Prompts:</strong> "3 bullets max", "table only", "JSON only", "one-line verdict + risk".</p>
<p><strong>Deliverable:</strong> team snippet library for common Copilot outputs.</p>
</div>
</section>
</section>
<section>
<section>
<p class="kicker">Part 2.5</p>
<h2>Workflow optimization</h2>
<p>Choose a lower-overhead workflow before shortening individual prompts.</p>
</section>
<section>
<h2>Commit and PR text matter</h2>
<div class="grid">
<div class="card">
<h3>Commit</h3>
<p><code>feat: add password reset via settings page</code></p>
<p>Body only when "why" is not obvious.</p>
</div>
<div class="card">
<h3>Review</h3>
<p><code>L42: bug: user can be null. Add guard before .email.</code></p>
<p>One-line, actionable, severity-coded.</p>
</div>
</div>
</section>
<section>
<h2>Ask vs Edit vs Agent</h2>
<img class="diagram diagram-compact" src="../docs/assets/diagrams/mode-decision-tree.svg" alt="Decision tree: use Ask for questions, Edit for targeted single-file changes, Agent for clear multi-file work, and clarify vague tasks first.">
</section>
<section>
<h2>Auto model default</h2>
<p>Auto is a good baseline: supported Auto pool, org policy-aware, discount on eligible paid-plan Chat usage per docs.</p>
<p class="warning">Auto does not mean "escalate into every premium model." Pin premium deliberately.</p>
</section>
<section>
<h2>Retune prompts when model changes</h2>
<pre><code class="language-text">Target model: GPT-5.5.
Guide: <official prompting guide URL>
Files: .github/copilot-instructions.md, .github/instructions/*.md
Adapt prompts to guide. Preserve behavior. Reduce rework.
Show diff only.</code></pre>
</section>
<section>
<h2>When not to compress</h2>
<ul>
<li>Security warnings.</li>
<li>Irreversible operations.</li>
<li>Onboarding and teaching.</li>
<li>Regulatory/compliance language.</li>
<li>Complex instructions where fragments add ambiguity.</li>
</ul>
</section>
<section>
<h2>Close loop with usage coaching</h2>
<div class="grid">
<div class="card">
<h3><code>/chronicle</code></h3>
<p>Copilot CLI session history (not VS Code). Use <code>/chronicle cost tips</code> for token spend and <code>/chronicle improve</code> for recurring confusion.</p>
</div>
<div class="card">
<h3>AI Engineering Coach</h3>
<p>VS Code local extension. Finds anti-patterns, context health, skill opportunities.</p>
</div>
</div>
</section>
<section>
<h2>Plan first, execute cheaply</h2>
<img class="diagram diagram-compact" src="../docs/assets/diagrams/plan-execute-cheaply.svg" alt="Plan with strong model, save plan, execute in fresh cheaper session, then verify acceptance criteria.">
</section>
<section>
<h2>Lab 8: mode routing drill</h2>
<div class="card lab">
<h3>Goal</h3>
<p>Stop using Agent Mode for one-shot work.</p>
<p><strong>Do:</strong> classify 20 sample tasks as Ask/Edit/Agent/Coding Agent. Defend choice.</p>
<p><strong>Deliverable:</strong> team mode-routing cheat sheet.</p>
<p><strong>Time:</strong> 20 minutes.</p>
</div>
</section>
<section>
<h2>Lab 9: model routing drill</h2>
<div class="card lab">
<h3>Goal</h3>
<p>Prevent expensive-model pinning by default.</p>
<p><strong>Do:</strong> map tasks to Auto, included/lower-cost, standard, premium. Include reasoning-effort choice if available.</p>
<p><strong>Deliverable:</strong> model escalation rules.</p>
</div>
</section>
</section>
<section>
<section>
<p class="kicker">Part 2.6</p>
<h2>Always-on context problem</h2>
<p>More context can make agents worse and cost more.</p>
</section>
<section>
<h2>Research signal</h2>
<table>
<thead><tr><th>Finding</th><th>Observed impact</th></tr></thead>
<tbody>
<tr><td>LLM-generated context files</td><td>Hurt in 5/8 settings</td></tr>
<tr><td>Average correctness</td><td>Down about 2%</td></tr>
<tr><td>Token cost</td><td>Up 20-23%</td></tr>
<tr><td>Reasoning overhead</td><td>Up about 22% in cited setup</td></tr>
</tbody>
</table>
</section>
<section>
<h2>Why context hurts</h2>
<div class="grid">
<div class="card"><h3>Redundancy</h3><p>Repeats facts the agent can find in code.</p></div>
<div class="card"><h3>Attention</h3><p>Buries important rules in long context.</p></div>
<div class="card"><h3>Anchoring</h3><p>Steers the agent toward outdated tools.</p></div>
<div class="card"><h3>Signal/noise</h3><p>Makes project-specific pitfalls harder to spot.</p></div>
</div>
</section>
<section>
<h2>Keep landmines only</h2>
<table>
<thead><tr><th>Keep</th><th>Delete</th></tr></thead>
<tbody>
<tr><td>Use <code>uv</code> instead of <code>pip</code></td><td>This is a Python project</td></tr>
<tr><td>DB migrations must run in order</td><td>We use PostgreSQL</td></tr>
<tr><td>Do not refactor auth module; audit pending</td><td>We use JWT auth</td></tr>
<tr><td>Deploy requires VPN</td><td>Main branch protected</td></tr>
</tbody>
</table>
</section>
<section>
<h2>Bug tracker model</h2>
<pre><code class="language-text">Start almost empty.
Agent trips on something -> add one line.
Root cause fixed -> delete that line.</code></pre>
<p>Remove instructions when the underlying problem is fixed.</p>
</section>
<section>
<h2>Lab 10: landmine pruning</h2>
<div class="card lab">
<h3>Goal</h3>
<p>Cut context without losing correctness.</p>
<p><strong>Do:</strong> mark each instruction as discoverable, style, landmine, stale, duplicate. Delete or scope everything except true always-on landmines.</p>
<p><strong>Deliverable:</strong> 10-line max instruction file draft.</p>
<p><strong>Time:</strong> 35 minutes.</p>
</div>
</section>
</section>
<section>
<section>
<p class="kicker">Part 2.7</p>
<h2>MCP and tool costs</h2>
<p>Loaded tool definitions add input, even when the tool is unused.</p>
<img class="diagram diagram-compact" src="../docs/assets/diagrams/mcp-tooling-stack.svg" alt="Tooling stack: scope MCP schemas, use CodeAct for turn loops, RTK or snip for output, Graphify for orientation.">
</section>
<section>
<h2>Measure first</h2>
<pre><code class="language-text">/context
System/Tools: MCPs + instructions + system prompt
Messages: conversation history
Free Space: remaining context</code></pre>
<p class="small">Inspect loaded tools. Installed server counts alone do not capture deferred definitions or cache behavior.</p>
</section>
<section>
<h2>Every tool costs tokens</h2>
<table>
<thead><tr><th>Component</th><th>Approx cost</th></tr></thead>
<tbody>
<tr><td>Name + description</td><td>20-50 tokens</td></tr>
<tr><td>Simple parameter schema</td><td>30-80 tokens</td></tr>
<tr><td>Complex parameter schema</td><td>100-300 tokens</td></tr>
<tr><td>Total per tool</td><td>100-500 tokens</td></tr>
</tbody>
</table>
</section>
<section>
<h2>Multiplication problem</h2>
<pre><code class="language-text">10 MCP servers
x 5 tools each
x 200 tokens/tool
= 10,000 tokens per step
15 agent steps = 150,000 schema tokens</code></pre>
<p class="small">Hypothetical full-catalog loading, not measured billing. Deferred definitions and caching change the result.</p>
</section>
<section>
<h2>Audit rule</h2>
<ul>
<li>Disable servers not needed now.</li>
<li>Use workspace settings for project-specific servers.</li>
<li>Prefer built-in tools over duplicate filesystem MCPs.</li>
<li>Use skills for occasional capabilities.</li>
<li>Scope large plugins by namespace/mode when supported.</li>
</ul>
</section>
<section>
<h2>Tool output compression</h2>
<div class="grid">
<div class="card">
<h3>RTK</h3>
<p>Rust CLI proxy filters noisy shell output: tests, git diff, grep, logs, file listings.</p>
<pre><code class="language-bash">rtk init --copilot</code></pre>
</div>
<div class="card">
<h3>snip</h3>
<p>YAML-extensible command filters with local savings stats and team-maintained rules.</p>
<pre><code class="language-bash">snip init --agent copilot</code></pre>
</div>
</div>
<p class="small warning">Pick one output filter layer per command path. Do not stack RTK and snip by default.</p>
</section>
<section>
<h2>One tool per layer</h2>
<table>
<thead><tr><th>Layer</th><th>Tool</th><th>Reduces</th></tr></thead>
<tbody>
<tr><td>Workflow turns</td><td>CodeAct</td><td>Repeated model-tool loops</td></tr>
<tr><td>Command output</td><td>RTK or snip</td><td>Verbose shell results</td></tr>
<tr><td>Command choice</td><td>minimal-context-tools</td><td>Broad search/read behavior</td></tr>
<tr><td>Codebase orientation</td><td>Graphify</td><td>Repeated file rereads</td></tr>
<tr><td>Visibility</td><td>Chronicle / Coach</td><td>Waste you would miss</td></tr>
</tbody>
</table>
</section>
<section>
<h2>Azure MCP case pattern</h2>
<p>One large plugin can account for most of the System/Tools context.</p>
<pre><code class="language-bash">--namespace appservice --namespace cosmos --namespace keyvault --namespace storage</code></pre>
<p class="small">Load the services each role needs. Avoid "all tools" mode unless the task requires it.</p>
</section>
<section>
<h2>Lab 11: MCP audit</h2>
<div class="card lab">
<h3>Goal</h3>
<p>Remove hidden schema overhead.</p>
<p><strong>Do:</strong> inventory enabled MCP servers, tool counts, global vs workspace scope, owner, frequency of use.</p>
<p><strong>Deliverable:</strong> keep/disable/scope table + restart plan.</p>
<p><strong>Time:</strong> 30 minutes.</p>
</div>
</section>
<section>
<h2>Enterprise lab: tool policy</h2>
<div class="card enterprise">
<h3>Customer-side action</h3>
<p>Define approved MCP servers by persona: developer, data, platform, security, support.</p>
<p><strong>Deliverable:</strong> default MCP profile per team + exception process for large plugins.</p>
</div>
</section>
</section>
<section>
<section>
<p class="kicker">Part 3</p>
<h2>Comparisons and data</h2>
<p>Compare measured effects with their baseline, workload, and limits.</p>
</section>
<section>
<h2>Same task, different cost</h2>
<table>
<thead><tr><th>Study</th><th>Control</th><th>Result</th></tr></thead>
<tbody>
<tr><td>Upstream</td><td>Answer concisely.</td><td>3% median output reduction; 10 prompts, one run</td></tr>
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