fix: sha256:64298d820f83e03ad4a1d3dae5a5fe2e57d124c1ebd0d56e99d93e69b595dccc · gabriel/musehub

fix: stdio MCP transport never created a session, breaking musehub_set_context's session focus (musehub#210)

musehub_set_context's own returned message tells every connecting agent to call it once and then omit owner/slug on subsequent calls -- the documented, intended workflow. The dispatcher's session-focus injection (_handle_tools_call, dispatcher.py) was never broken: it correctly writes to session.repo_focus and correctly injects it into the next call's arguments when owner/slug are absent. The bug was entirely in musehub/mcp/stdio_server.py -- every handle_request() call passed session=None (the implicit default), so musehub_set_context's write was a silent no-op (guarded by an is-not-None check on ctx.session), and the next musehub_read_context() call had no session to inject owner/slug from, resolving to an empty-string repository lookup.

The Streamable HTTP transport never had this problem: it creates an MCPSession right after a successful initialize and threads it through every subsequent request via the Mcp-Session-Id header. stdio has no such header, but it IS a single, long-lived connection to exactly one client for the process's lifetime -- so the fix creates one session at the same moment HTTP does (right after a successful initialize) and reuses that same object for every request thereafter, for as long as the process runs.

Extracted the capability-extraction + create_session() logic HTTP already had (_create_session_from_initialize in api/routes/mcp.py) into a shared musehub.mcp.session.create_session_from_initialize_params(), used by both transports now instead of duplicating it.

+17

symbols added

symbols modified

−2

symbols removed

files changed

1110

files in snapshot

dead code introduced

Semantic Changes 28 symbols

~ tests/test_mcp_stdio_session.py .py 15 symbols added

+ TestStdioSessionPersistence class class TestStdioSessionPersistence L79–154

+ test_session_is_reused_not_recreated_per_message method async_method test_session_is_reused_not_recreated_per_message L124–154

+ test_set_context_then_read_context_resolves_focused_repo method async_method test_set_context_then_read_context_resolves_focused_repo L80–122

+ _FakeWriteTransport class class _FakeWriteTransport L27–37

+ __init__ method method __init__ L30–31

+ lines method method lines L36–37

+ write method method write L33–34

+ _run_stdio_with_lines function async_function _run_stdio_with_lines L40–75

+ AsyncMock import import AsyncMock L22–22

+ MagicMock import import MagicMock L22–22

+ annotations import import annotations L18–18

+ asyncio import import asyncio L20–20

+ json import import json L21–21

+ patch import import patch L22–22

+ pytest import import pytest L24–24

~ musehub/api/routes/mcp.py .py 1 symbol added, 2 symbols removed, 8 symbols modified

− _create_session_from_initialize function function _create_session_from_initialize L554–565

− create_session import import create_session L47–47

+ create_session_from_initialize_params import import create_session_from_initialize_params L47–47

~ MCPSession

~ SessionCapacityError

~ delete_session

~ get_session

~ push_to_session

~ register_sse_queue

~ resolve_elicitation

~ mcp_post

~ musehub/mcp/session.py .py 1 symbol added

+ create_session_from_initialize_params function function create_session_from_initialize_params L153–169

~ musehub/mcp/stdio_server.py .py 1 symbol modified

~ _run

Files Changed

+1 ~3

1110 in snapshot

+ tests/test_mcp_stdio_session.py .py

~ musehub/api/routes/mcp.py .py

~ musehub/mcp/session.py .py

~ musehub/mcp/stdio_server.py .py

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