AI agents increasingly read your docs instead of a human. If your documentation site only emits HTML for a browser, an agent has to scrape and guess. There's a better surface — and most of it is a handful of small, standard files. Here's the full stack we ship on the OrchestKit docs site, why each piece exists, and how to verify it.

1. llms.txt — the agent's table of contents

A plain-text index at /llms.txt: what the product is, its constraints, and a link map to every machine-readable resource. Keep it under ~30k chars; put the exhaustive page list in /docs/llms.txt and the full corpus in /llms-full.txt. The win: an agent gets oriented in one fetch instead of crawling.

2. Markdown content negotiation

Append .md to any page URL (or send Accept: text/markdown) and return the raw Markdown. Agents get clean tokens; humans still get the rendered page.

3. An OpenAPI spec for your read APIs

Even a docs site has an API surface (search, page fetch). Publish an OpenAPI document at a predictable path so an agent can call it without reverse-engineering. Pair it with RFC 9727 — a /.well-known/api-catalog linkset that enumerates every API entry point.

4. An MCP server

The Model Context Protocol lets agents call your tools natively. We expose a read-only MCP server over Streamable HTTP at /api/mcp plus a discovery server-card.json. Two tools — search docs, get a doc by id — are enough to be useful.

5. The .well-known identity files

• agent-card.json (A2A): declares your agent skills.
• agent-skills/index.json: the Agent Skills Discovery RFC, with a SHA-256 digest per skill so a consumer can verify it.
• oauth-protected-resource (RFC 9728): if your API is anonymous, say so — an empty authorization_servers is a positive signal, not an omission.

6. JSON-LD that an entity graph can reconcile

Emit a schema.org graph (Organization, SoftwareApplication, WebSite) linked by @id, with sameAs pointing at the registries that already verify you (GitHub, your package registry, Wikidata). One canonical Organization block, reused everywhere, so the graph never sees conflicting identifiers. Never fabricate an aggregateRating — surface real signals (e.g. GitHub stars as an InteractionCounter) instead.

7. Tell crawlers the truth in robots.txt

Explicitly allow the named AI crawlers you want (GPTBot, ClaudeBot, OAI-SearchBot, Google-Extended…), and emit a Content-Signal directive. Link your sitemap and a schema-map.

How to verify

curl -s https://yoursite/llms.txt, fetch each .well-known path, and run your JSON-LD through a structured-data validator. If you build on Claude Code, the open-source OrchestKit docs site implements every item above — the source is on GitHub, MIT-licensed, and you can read the route handlers directly.

I maintain OrchestKit (a free, MIT plugin for Claude Code, 111 skills/37 agents/210 hooks). The agent-discovery surface described here is what its docs site ships today.