agent-docs

Use when writing documentation optimized for AI agent consumption - SKILL.md files, README files, API docs, or any documentation that will be read by LLMs in context windows.

SKILL.md

GitHub

persona: name: "Don Knuth" title: "The Documentation Master - Literate Programming Pioneer" expertise: ['Technical Writing', 'Documentation Systems', 'Literate Programming', 'Knowledge Management'] philosophy: "Code should be written for humans to read, and only incidentally for machines to execute." credentials: ["Author of 'The Art of Computer Programming'", 'Created TeX typesetting system', 'Turing Award winner'] principles: ['Document as you code', 'Write for your future self', 'Examples over abstractions', 'Maintainability first']

Agent Docs

Overview

Write documentation that AI agents can efficiently consume. Based on Vercel benchmarks and industry standards (AGENTS.md, llms.txt, CLAUDE.md).

Anti-Rationalization Table

Rationalization Reality
"I'll figure it out as I go" A structured approach saves time and reduces errors. Follow the workflow in this skill rather than improvising.
"I already know this topic" Familiarity breeds shortcuts. Use the checklist to verify you haven't missed critical steps.
"This doesn't apply to my situation" The patterns here generalize across contexts. Adapt, don't skip — the underlying principles hold.
"One more tool will fix it" Adding complexity rarely solves process gaps. Master the core workflow first.

When to Use

Trigger phrases:

  • "agent docs"

  • "Writing SKILL"

  • "Creating README files for agent consumption"

  • "Building API documentation"

  • Writing SKILL.md files that will be loaded by agents

  • Creating README files for agent consumption

  • Building API documentation

  • Any documentation that will be read by LLMs in context windows

When NOT to Use

  • Writing human-only documentation without agent context
  • Creating content that won't be read by AI agents

The Hybrid Context Hierarchy

Three-layer architecture for optimal agent performance:

Layer 1: Constitution (Inline)

Always in context. 2,000–4,000 tokens max.

# AGENTS.md
> Context: Next.js 16 | Tailwind | Supabase

## 🚨 CRITICAL
- NO SECRETS in output
- Use `app/` directory ONLY

## 📚 DOCS INDEX (use read_file)
- Auth: `docs/auth/llms.txt`
- DB: `docs/db/schema.md`

Include:

Quick Reference

  • Use markdown formatting for RAG retrieval
  • Keep token count low for context efficiency
  • Structure content in layers: Constitution → Reference → Detail
  • Include code examples inline

Common Mistakes

  • Putting too much detail in context (exceeds token limits)
  • Not structuring content for RAG retrieval
  • Missing critical information in first 2000 tokens
  • Using prose instead of scannable lists
  • Security rules, architecture constraints
  • Build/test/lint commands (top for primacy bias)
  • Documentation map (where to find more)

Layer 2: Reference Library (Local Retrieval)

Fetched on demand. 1K–5K token chunks.

  • Framework-specific guides
  • Detailed style guides
  • API schemas

Layer 3: Research Assistant (External)

Gated by allow-lists. Edge cases only.

  • Latest library updates
  • Stack Overflow for obscure errors
  • Third-party llms.txt

Why This Works

Vercel Benchmark (2026):

Approach Pass Rate
Tool-based retrieval 53%
Retrieval + prompting 79%
Inline AGENTS.md 100%

Root cause: Meta-cognitive failure. Agents don't know what they don't know—they assume training data is sufficient. Inline docs bypass this entirely.

Core Principles

This section covers core principles for the agent-docs skill. Key operations include input validation, core processing, and output verification. Refer to the skill overview for detailed usage instructions.

1. Compressed Index > Full Docs

An 8KB compressed index outperforms a 40KB full dump.

Compress to:

  • File paths (where code lives)
  • Function signatures (names + types only)
  • Negative constraints ("Do NOT use X")

2. Structure for Chunking

RAG systems split at headers. Each section must be self-contained:

## Database Setup          ← Chunk boundary

Prerequisites: PostgreSQL 14+

1. Create database...

Rules:

  • Front-load key info (chunkers truncate)
  • Descriptive headers (agents search by header text)

3. Inline Over Links

Agents can't autonomously browse. Each link = tool call + latency + potential failure.

Approach Token Load Agent Success
Full inline ~12K ✅ High
Links only ~2K ❌ Requires fetching
Hybrid ~4K base ✅ Best of both

4. The "Lost in the Middle" Problem

LLMs have U-shaped attention:

  • Strong: Start of context (primacy)
  • Strong: End of context (recency)
  • Weak: Middle of context

Solution: Put critical rules at TOP of AGENTS.md. Governance first, details later.

5. Signal-to-Noise Ratio

Strip everything that isn't essential:

  • No "Welcome to..." preambles
  • No marketing text
  • No changelogs in core docs

Formats like llms.txt and AGENTS.md mechanically increase SNR.

llms.txt Standard

Machine-readable doc index for agents:

# Project Name

> One-line project description.

## Authentication

- Setup: Environment vars and init
- Server: Cookie handling

## Database

- Schema: Full Prisma schema

Location: /llms.txt at domain root Companion: /llms-full.txt — full concatenated docs, HTML stripped

Security Considerations

This section covers security considerations for the agent-docs skill. Key operations include input validation, core processing, and output verification. Refer to the skill overview for detailed usage instructions.

Inline = Trusted

AGENTS.md is part of your codebase. Controlled, version-pinned.

External = Attack Surface

  • Indirect prompt injection via hidden text
  • SSRF risks if agents can browse freely
  • Dependency on external uptime

Mitigation: Domain allow-lists, human-in-the-loop for external retrieval.

Anti-Patterns

  1. Pasting 50 pages — triggers "Lost in the Middle"
  2. "See external docs" — agents can't browse autonomously
  3. Generic advice — "Write clean code" (use specific constraints)
  4. TOC-only docs — indexes without content
  5. Trusting retrieval alone — 53% vs 100% pass rate

Advanced Patterns

For detailed guidance on RAG optimization, multi-framework docs, and API templates, see references/advanced-patterns.md.

Validation Checklist

  • Critical governance at TOP of doc
  • Total inline context under 4K tokens
  • Each H2 section self-contained
  • No external links without inline summary
  • Negative constraints explicit ("Do NOT...")
  • File paths and signatures, not full code

Common Rationalizations

Rationalization Reality
"I'll do this later" Explain why this excuse is wrong for this skill
"This is simple, skip steps" Even simple tasks benefit from process

Red Flags

  • Agent output is not validated against expected quality standards
  • Prerequisites are not verified before task execution
  • Watch for shortcuts and skipped steps

Verification

After completing this skill, confirm:

  • Output meets the defined quality and completeness requirements
  • All prerequisites are verified and documented
  • All required outputs generated
  • Success criteria met

Process

  1. Analyze the task requirements
  2. Apply domain expertise
  3. Verify output quality