* fix(agentctl): reap disconnected ACP sessions + MCP child trees (#1247)
Two independent leaks let opencode acp sessions accumulate indefinitely:
1. instance.Manager never reaped disconnected sessions. StopInstance
only ran via the kandev DELETE route, so any session whose backend
went away (UI closed mid-run, WS dropped, opencode failed to emit
complete) was orphaned forever.
2. Even when DELETE fired, the ACP adapter unconditionally returned
RequiresProcessKill=false. opencode acp keeps an HTTP server + MCP
child tree alive after stdin EOF, so closing stdin was a no-op and
the children re-parented to init.
Fix both:
- Plumb RuntimeConfig.RequiresProcessKill from agents.OpenCodeACP
through the ExecutorCreateRequest -> CreateInstanceRequest ->
InstanceConfig -> adapter.Config -> shared.Config chain. acp.Adapter
now reads cfg.RequiresProcessKill instead of hardcoding false.
- Belt-and-braces: process.Manager.waitForProcessExit timeout fallback
now killProcessGroup first (only falls back to single-process kill
if that errors), so any future ACP CLI that ignores stdin EOF still
gets reaped.
- Add an idle-instance reaper to instance.Manager. Per-instance
activity middleware tracks inflight HTTP requests + lastActivity;
a background goroutine sweeps every minute and StopInstance's any
instance idle past KANDEV_ACP_IDLE_TIMEOUT (default 1h, set to 0
to disable). Long-lived /agent/stream WS connections keep the
inflight counter above zero so active sessions are never reaped.
- Validate stdio MCP commands at CreateInstance time via
exec.LookPath; missing entries are dropped with a warn instead of
spawning a permanently broken child every session (fixes the
stale /snap/bin/brave MCP repro in the issue).
Regression tests: process-group kill (parent+child fixture), idle
reaper end-to-end, MCP validation, opencode-acp opt-in vs other
ACP agents' default.
* fix: address PR review feedback on #1247 fix
- idle_reaper: extract reapSingleIdleInstance helper with defer cancel(),
add reaperStop polling between sweep iterations so Shutdown drains in
one StopInstance window instead of N * timeout (cubic, claude, greptile).
- instance.Manager: use sync.Once instead of m.mu to gate reaper-stop
channel close (claude).
- mcpStdioValidationError: tolerate compound Command strings by
resolving only the first whitespace-delimited token; reject entries
with neither URL nor Command outright; document agentctl-vs-agent
PATH skew in Docker/SSH executor modes (claude, greptile, cubic).
- manager_killgroup_test: treat zombie state as dead via /proc/<pid>/stat
on Linux + bump Eventually window to 15s — CI containers' PID 1 can
delay harvesting orphans long enough to flake signal(0) probes.
- instance package: add goleak TestMain for the new reaper goroutine
(coderabbit).
- AGENTS.md: correct SIGKILL vs SIGTERM wording; clarify the timeout
fallback only fires on ctx.Done (coderabbit, cubic).
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Co-authored-by: Kandev Agent <agent@kandev.dev>
Carlos Florêncio