Relationship to MCP

MCP (Model Context Protocol) standardizes how a model talks to tools. ECP (Execution Control Protocol) standardizes how an agent delegates a governed graph of those tools. They stack:

MCP exposes tools (and, later, ECP itself as an MCP server).
The orchestrating agent reasons about an approach.
The agent authors a *.ecp.ts workflow and runs it through the ECP CLI.
ECP records a journal, returns structured errors, and lets the agent repair and rerun.

Complementary, not competing

Layer	Job
MCP	Discover and call tools from a model session
ECP	Compile, validate, govern, journal, and rerun a workflow

Use MCP when the model should poke at a live tool. Use ECP when the sequence should be portable, policy-bound, and replayable.

MCP as an ECP plugin

ecp mcp serve exposes the same host as the CLI: meta tools plus one tool per installed capability. See MCP for stdio, HTTP, tool names, and client snippets.

Next steps

Why ECP
MCP