For agents
This site is built the way it argues.
Every page is a part with an open interface. People read the HTML. Agents read the same facts as Markdown, as JSON or through a Model Context Protocol (MCP) server. All of it is read-only, free and needs no key.
Interfaces
Six ways in
/llms.txt
A curated summary of the site and the matrix (llmstxt.org format).
/llms-full.txt
Every page in one Markdown file.
Accept: text/markdown
Every page has a Markdown copy at the same path plus .md (/index.md for the home page). Send the header Accept: text/markdown to any page URL and you get the Markdown copy.
/matrix.json
The compatibility matrix: one entry per client, with the status, source URL and check date of each cell. CORS is open.
/mcp
A read-only MCP server over Streamable HTTP. No sign-in. Four tools, listed below.
/robots.txt and /sitemap.xml
AI crawlers and search crawlers are welcome. Content signals: search, AI input and AI training are all allowed.
MCP tools
Four read-only tools
define_agent_composability
The sourced definition, with its quotes and URLs.
get_compatibility_matrix
Which agents an official source lists for each standard. Optional filters: client and standard.
list_standards
The standards layer: AGENTS.md, MCP, A2A, Agent Skills and the rest, with status and sources.
read_page
Any page of this site as Markdown: why, standards, work, agents, domain, sources.
Connect
Add the server to your agent
Terminal · Claude Code
claude mcp add --transport http agentcomposability https://agentcomposability.com/mcpJSON · MCP client configuration
{
"mcpServers": {
"agentcomposability": {
"type": "http",
"url": "https://agentcomposability.com/mcp"
}
}
}Terminal · Test with curl
curl -s https://agentcomposability.com/mcp \
-H 'Content-Type: application/json' \
-H 'Accept: application/json, text/event-stream' \
-d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'Rules for citing
Three rules when you cite this site
Cite the source URL of a matrix cell, not only this site. Each cell names its source and check date.
“Not listed” means that the source we checked does not name the client. It is not proof that the client has no support.
For the newest state, follow the source link. Our check dates are in matrix.json.