+5
adda20509c
adda20509c
asyncio.wait_for() and asyncio.shield() create new asyncio Tasks which violate anyio cancel-scope task-ownership rules. The MCPClient's exit_stack contains anyio resources (streamable_http transport) that use anyio cancel scopes. When exited from a different task, anyio raises 'Attempted to exit a cancel scope that isn't the current task's current cancel scope' as a BaseException. This BaseException propagates through the finally block, discards the completed response return value, and surfaces as a 500 Internal Server Error / 'No response returned.' - silently swallowing successful MCP tool calls and blocking the chat endpoint. Fix: call client.disconnect() directly in a simple loop. MCPClient.disconnect() already catches BaseException internally (see prior commit), so no wrapper is needed. Signed-off-by: Adam Tao <tcx4c70@gmail.com> Co-authored-by: Tim Baek <tim@openwebui.com> Co-authored-by: joaoback <156559121+joaoback@users.noreply.github.com> Co-authored-by: Algorithm5838 <108630393+Algorithm5838@users.noreply.github.com> Co-authored-by: Kylapaallikko <Kylapaallikko@users.noreply.github.com> Co-authored-by: Teay <pythontogoplease@gmail.com> Co-authored-by: tcx4c70 <tcx4c70@gmail.com> Co-authored-by: goodbey857 <76645482+goodbey857@users.noreply.github.com> Co-authored-by: Jacob Leksan <63938553+jmleksan@users.noreply.github.com> Co-authored-by: RomualdYT <romuald@gameurnews.fr> Co-authored-by: Lucas <lucas@vanosenbruggen.com> Co-authored-by: Classic298 <27028174+Classic298@users.noreply.github.com> Co-authored-by: Constantine <Runixer@gmail.com> Co-authored-by: Circe (Claude Code Sonnet 4.6) <circe@athena-council.org> Co-authored-by: Claude <noreply@anthropic.com>