MCP Tool Manifest¶

Raw manifest: manifest.json

Launching the server¶

Start the server over stdio with a rule pack (needs the mcp and cli extras):

fathom mcp path/to/rules

The pack is compiled before the server starts: a broken pack exits 1, an unreadable one 2. Once serving, stdout carries the MCP protocol. To register it with an MCP client, give the client that command, e.g.:

{"mcpServers": {"fathom": {"command": "fathom", "args": ["mcp", "path/to/rules"]}}}

Only stdio is supported. The tools are unauthenticated and share one Engine, so each client gets its own server process. From Python, FathomMCPServer(rules_path).run() (fathom.integrations.mcp_server) does the same.

Tools¶

Tool	Description
`fathom.agenda`	List the activations waiting to fire
`fathom.assert_fact`	Assert a fact into working memory
`fathom.evaluate`	Run forward-chain evaluation
`fathom.query`	Query working memory
`fathom.retract`	Retract facts from working memory
`fathom.rule_matches`	Report how far a rule got toward firing: matches, partials, activations
`fathom.trace`	Evaluate and return the decision with every rule firing in order