TL;DR

Wire cleanupBundleMcpOnRunEnd: true into the sessions_spawn run path to ensure bundle MCP child processes are reaped after a spawned run ends.

Guidance

• Review the src/agents/pi-embedded-runner/run.ts file, specifically lines 2062-2070, to understand the current implementation of disposeSessionMcpRuntime().
• Verify that setting cleanupBundleMcpOnRunEnd: true in src/commands/agent-via-gateway.ts for local one-shot runs correctly reaps bundle MCP child processes.
• Update the sessions_spawn path to include cleanupBundleMcpOnRunEnd: true, mirroring the pattern in agent-via-gateway.ts, to ensure consistent behavior for spawned runs.
• Test the updated implementation to confirm that bundle MCP child processes are properly reaped after a spawned run ends, regardless of cleanup mode.

Example

No code snippet is provided as the issue already suggests a specific fix and the code changes are implied.

Notes

The suggested fix assumes that the cleanupBundleMcpOnRunEnd flag is the primary mechanism for controlling the reaping of bundle MCP child processes. If other factors are at play, additional investigation may be necessary.

Recommendation

Apply the workaround by wiring cleanupBundleMcpOnRunEnd: true into the sessions_spawn run path, as this directly addresses the identified root cause and is expected to resolve the issue.