docs(state): seed subagent reliability investigation

WIP.subagent-reliability.md

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+# WIP.subagent-reliability.md
+
+## Status
+Status: `open`
+Owner: `zap`
+Opened: `2026-03-13`
+
+## Purpose
+Investigate and improve subagent / ACP delegation reliability, including timeout behavior, runtime failures, and delayed/duplicate completion-event noise.
+
+## Why now
+This is the highest-leverage remaining open reliability item because it affects trust in delegation and the usability of fresh implementation runs.
+
+## Related tasks
+- `task-20260304-2215-subagent-reliability` — in progress
+- `task-20260304-211216-acp-claude-codex` — open
+
+## Known context
+- Prior work already patched TUI formatting to suppress internal runtime completion context blocks.
+- Upstream patch exists in `external/openclaw-upstream` on branch `fix/tui-hide-internal-runtime-context` commit `0f66a4547`.
+- User explicitly wants subagent tooling reliability fixed and completion-event spam prevented.
+- Fresh-session implementation discipline and monitoring thresholds were already documented locally.
+
+## Goals for this pass
+1. Establish the current failure modes with concrete evidence.
+2. Separate ACP-specific failures from generic subagent/session issues.
+3. Determine what is already fixed versus still broken.
+4. Produce a concrete recommendation and, if feasible in one pass, implement the highest-confidence fix.
+5. Update task/memory state with evidence before ending.
+
+## Suggested investigation plan
+1. Review current OpenClaw docs and local memory around subagent/ACP failures.
+2. Reproduce or inspect recent failures using session/task evidence instead of guessing.
+3. Check current runtime status / relevant logs / known local patches.
+4. If the issue is in OpenClaw core, work in `external/openclaw-upstream/` on a focused branch.
+5. Validate with the smallest reliable reproduction possible.
+
+## Evidence gathered so far
+- Fresh subagent run failed immediately with provider auth error for `zai` before any task execution.
+- Current installed agent auth profiles include `openai-codex:default`, `litellm:default`, and `github-copilot:github`; there is no `zai` profile configured.
+- Root cause for this immediate repro appears to be an incorrect explicit spawn model choice (`glm-5` alias → `zai/glm-5`) rather than missing auth propagation between agents.
+- Next step after confirming the model-selection issue: prefer `gpt-5.4` for fresh subagent reliability/debug passes for now, per Will's instruction, and continue separating real runtime issues from operator/config mistakes.
+
+## Constraints
+- Prefer evidence over theory.
+- Do not claim a fix without concrete validation.
+- Keep the main session clean; use this file as the canonical baton.
+
+## Success criteria
+- Clear diagnosis of the current reliability problem(s).
+- At least one of:
+  - implemented fix with validation, or
+  - sharply scoped next fix plan with exact evidence and files.
+- `memory/2026-03-13.md` (or current daily note), `memory/tasks.json`, and this WIP updated.