Manifest fields

The ExtensionManifest struct is the shape. A field that struct does not accept does not exist.

{
  "schema": "koma-extension/v0",
  "id": "run.koma.example.echo-tool-daemon",
  "name": "Echo Tool",
  "version": "0.0.0",
  "description": "One sentence a person can read.",
  "tier": "free",
  "kind": "daemon",
  "runtime": { "exec": "echo-tool-daemon", "args": [] },
  "contributes": {},
  "requires": [],
  "workspace_dir": "/absolute/path/this-extension-owns",
  "mcp_servers": []
}

schema is koma-extension/v0 today.

id is reverse-DNS and stable for the life of the extension.

name is the label a person sees.

version is your version string.

description is one sentence.

tier is free or paid.

kind is daemon or oneshot.

runtime.exec is the binary name. runtime.args is an array.

contributes is what Koma may call you for. Leave it out to contribute nothing.

requires is the grant strings you need. Leave it out to call nothing.

workspace_dir is a directory you own. Koma injects it as a writable root on every session that activates you. It is not a path you pass on each spawn.

mcp_servers are MCP servers that belong to you. They install and leave with the extension.

A sub-agent in the manifest may list a tools allow-list. It also inherits MCP tools that are connected. A model slug on a sub-agent resolves through the catalogue, including models you register at runtime. The manifest entry is not itself a served model. Serving models is models.register, which needs the models:contribute grant and a connected account or key.