PR #70306: fix(acp+gateway): clean final emit, fallback visibility, legacy unit resolve

• Repository: openclaw/openclaw
• Author: nrubioru
• State: open | merged: False
• Link: https://github.com/openclaw/openclaw/pull/70306

Description (problem / solution / changelog)

Problem

Three related rough edges in ACP/Codex orchestration and gateway ops:

1. Parent sessions could fail to surface a coherent final answer after sessions_spawn(runtime="acp"). Mid-flight snippet flushes compacted whitespace and truncated aggressively, so short multi-line Codex key/value output could collapse into a single line before any clean final answer reached the parent.
2. Harness fallback visibility was weak. Operators could not easily answer "did this actually run in Codex or fall back?" without grepping logs.
3. Legacy hosts running clawdbot-gateway.service exposed CLAWDBOT_SYSTEMD_UNIT, but the relevant resolver paths only honored OPENCLAW_SYSTEMD_UNIT, so status/restart tooling could target the canonical openclaw-gateway.service instead of the actual running unit.

Solution

• src/agents/acp-spawn-parent-stream.ts
  • Accumulate non-commentary child output into a dedicated final buffer.
  • On phase === "end", emit a single normalized <agent> final: system event with preserved newlines, line-aware truncation, and whitespace cleanup.
  • On phase === "error", surface the partial transcript before the error text.
  • Keep the existing mid-flight snippet behavior for progress chatter.
• src/agents/harness/selection.ts
  • Record a 16-slot in-memory ring of harness selection diagnostics with requested runtime, selected harness, fallback usage, and reason.
• src/auto-reply/reply/commands-acp/diagnostics.ts
  • Extend /acp doctor to show recent harness selections, recent harness fallbacks, and the last 5 diagnostic entries.
• src/daemon/systemd.ts and src/cli/update-cli/restart-helper.ts
  • Fall back to CLAWDBOT_SYSTEMD_UNIT when OPENCLAW_SYSTEMD_UNIT is unset so legacy hosts resolve the actual running unit correctly.

Files changed

• src/agents/acp-spawn-parent-stream.ts
• src/agents/acp-spawn-parent-stream.final-output.test.ts (new)
• src/agents/harness/selection.ts
• src/agents/harness/selection.test.ts
• src/auto-reply/reply/commands-acp/diagnostics.ts
• src/cli/update-cli/restart-helper.ts
• src/cli/update-cli/restart-helper.test.ts
• src/daemon/systemd.ts

Tests run

• pnpm test src/agents/acp-spawn-parent-stream.test.ts
• pnpm test src/agents/acp-spawn-parent-stream.final-output.test.ts
• pnpm test src/agents/harness/selection.test.ts
• pnpm test src/auto-reply/reply/commands-acp.test.ts
• pnpm test src/cli/update-cli/restart-helper.test.ts
• pnpm test src/daemon/inspect.test.ts
• pnpm tsgo
• pnpm format:check on touched files
• repo pre-commit hook (oxlint / oxfmt) clean

Limitations

• Parent follow-through is mitigated, not fully fixed.
• sessions_spawn(runtime="acp") still returns an accepted envelope immediately; the clean child final reaches the parent via the relay side-channel rather than the tool result itself.
• A true attach-and-wait or resume-on-child-completion primitive would be a larger behavior change and should land separately.
• The new smoke coverage is unit-test based, not a live Codex roundtrip.
• The harness diagnostic ring is process-local and resets on gateway restart.
• Docs / changelog are not updated here.

Explicit note on parent follow-through

This change substantially improves the normal-path symptom where the parent appeared to "move on" without surfacing a clean final answer. The relay now emits a coherent final system event on completion, and the compact-whitespace collapse bug is covered by tests. However, the underlying architecture is unchanged: if the parent stops generating before the child-completion event arrives, the parent can still appear to move on. A true fix requires a larger orchestration change.

Changed files

• src/agents/acp-spawn-parent-stream.final-output.test.ts (added, +224/-0)
• src/agents/acp-spawn-parent-stream.ts (modified, +73/-2)
• src/agents/harness/selection.test.ts (modified, +57/-1)
• src/agents/harness/selection.ts (modified, +58/-0)
• src/auto-reply/reply/commands-acp/diagnostics.ts (modified, +26/-0)
• src/cli/update-cli/restart-helper.test.ts (modified, +14/-0)
• src/cli/update-cli/restart-helper.ts (modified, +8/-0)
• src/daemon/systemd.ts (modified, +11/-0)