fix: exit orphaned stdio MCP servers on parent death - #23
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Clients can abandon sessions while a wrapper keeps stdin open, so EOF never arrives and leaked servers thrash swap. Add a parent-liveness watchdog (same approach as mcp-automem).
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Capture os.getppid() before any await and pass it into the watchdog. Soft stdin EOF remains intentional (no hard-exit on EOF alone); hard exit stays on parent reparent / OS signals.
The parent_watchdog import was inserted inside the parenthesized tools import, which made server.py invalid Python. Move it above the block.
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Reviewed commit: 3b0c9f1027
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Capture os.getppid() after imports but before FastMCP/tool registration so the watchdog cannot pin a reparented pid. Fix parent_watchdog import lint.
CI ruff format --check requires double quotes on the install call.
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Summary
Stdio MCP servers can leak forever when a client (Claude Desktop / Cursor / Grok / Codex) abandons a session but an intermediate wrapper keeps the stdin write-end open. No EOF arrives, the process stays alive, and repeated leaks cause multi-GB swap thrashing.
This adds a parent-liveness watchdog (same approach as mcp-automem): when
ppid/os.getppid()changes from the startup parent (POSIX reparent), exit promptly.Test plan