{"repo":"NousResearch/hermes-agent","public_id":"63892","display_label":"MCP poll loop TimeoutError spin causing gateway OOM","summary":"Multiple fixes targeting an MCP poll loop bug where a completed future's real TimeoutError is mistaken for a poll timeout, causing infinite spinning and significant memory leakage. Several approaches to stopping the spin and surfacing the correct error are represented.","subsystem":"mcp","counts":{"members":6,"open_issues":0,"open_issues_distinct":0,"open_prs":0,"closed_issues":1,"merged_prs":1,"attempt_prs":4},"landed_fix":{"status":"merged_to_main","basis":"structural","pr":67183},"resolution":{"state":"resolved","by":"pr-67183"},"freshness":{"state":"verified","last_verified_at":"2026-07-18T22:55:27+00:00","is_stale":false},"grouping":{"backbone":"STRUCTURAL_SPANNING","link_density":0.3333333333333333},"fix_edges":[{"issue_number":63892,"pr_number":67183,"tier":"verified","basis":"closing_ref","confidence":0.95,"recoverable_from_timeline":true}],"members":[{"kind":"issue","number":63892,"title":"gateway OOM: MCP poll loop mistakes a completed future's real TimeoutError for a poll timeout (Py>=3.8 alias) and spins, leaking ~108MB/s of traceback","url":null,"state":"closed"},{"kind":"pr","number":63903,"title":"fix(mcp): resolve completed future in poll loop to stop TimeoutError spin (#63892)","url":null,"state":"closed","close_reason":{"refs":[{"kind":"pr","value":"#67183","number":67183}],"category":"implemented_elsewhere","implication":"superseded"},"merged":false},{"kind":"pr","number":63918,"title":"fix(mcp): propagate stored timeouts from completed futures","url":null,"state":"closed","close_reason":{"refs":[{"kind":"pr","value":"#67183","number":67183}],"category":"merged_via","implication":"superseded"},"merged":false},{"kind":"pr","number":64072,"title":"fix(mcp): surface completed future's real TimeoutError instead of spinning (_run_on_mcp_loop, #63892)","url":null,"state":"closed","close_reason":{"refs":[{"kind":"pr","value":"#67183","number":67183}],"category":"implemented_elsewhere","implication":"superseded"},"merged":false},{"kind":"pr","number":66039,"title":"fix: prevent OOM from MCP poll loop swallowing real TimeoutError (#63892)","url":null,"state":"closed","close_reason":{"refs":[{"kind":"pr","value":"#67183","number":67183},{"kind":"pr","value":"#63892","number":63892}],"category":"superseded_by_pr","implication":"superseded"},"merged":false},{"kind":"pr","number":67183,"title":"fix(mcp): stop gateway OOM from poll loop swallowing a completed future's real TimeoutError (supersedes #63918, #64072, #63903, #66039)","url":null,"state":"merged","close_reason":{"category":"merged","implication":"superseded"},"merged":true,"is_fix_pr":true,"fix_tier":"verified","files_changed":["tests/tools/test_mcp_poll_loop_oom_integration.py","tests/tools/test_mcp_tool.py","tools/mcp_tool.py"]}],"trust":{"default_tier":"verified","includes_suggested":false}}