MCP adapter

Mount rungent.mcp.create_mcp_asgi next to the product FastAPI router. The adapter invokes @tool functions directly. It does not start a Runtime session, emit ACS events, or run the model loop.

from fastapi import FastAPI, Request

from rungent import Identity
from rungent.fastapi import create_router
from rungent.mcp import create_mcp_asgi


async def resolve_identity(request: Request) -> Identity:
    user = await current_user(request)
    return Identity(subject_id=user.id, tenant_id=user.tenant_id)


app = FastAPI()
app.include_router(
    create_router(runtime, identity_resolver=resolve_identity),
    prefix="/api/assistant",
)
app.include_router(
    create_mcp_asgi(
        agent,
        identity_resolver=resolve_identity,
        context_factory=mcp_deps,
        resource_metadata_url="https://example.com/.well-known/oauth-protected-resource",
    ),
    prefix="/mcp",
)

Use the same Agent and the same @tool implementations. Pass tools= when the external catalog must be a subset (hide open_page and every requires_interaction_response continuation).

Behavior

Unauthenticated POST /mcp returns 401 with WWW-Authenticate: Bearer … resource_metadata="…". OAuth discovery and login belong to the host application. See External agents.

Agent.export_skill() writes a SKILL.md draft from exportable tools. Rewrite the voice and auth steps in the host product; do not ship the in-app system prompt as a Skill.