feat: add harness skill with hooks install/uninstall support (#156)

Add multi-session autonomous agent harness with progress checkpointing,
failure recovery, task dependencies, and post-completion self-reflection.

- Add harness module to config.json (copy_dir with hooks.json)
- Add 7 hook scripts: stop, sessionstart, teammateidle, subagentstop,
  claim, renew, self-reflect-stop + shared _harness_common.py
- Fix self-reflect-stop: only triggers when harness was initialized
  (checks harness-tasks.json existence), not on every session
- Add unmerge_hooks_from_settings() to uninstall.py for clean hook removal
- Add unit tests (57 tests) and E2E test (100 tasks + 5 self-reflect)

Generated with SWE-Agent.ai

Co-Authored-By: SWE-Agent.ai <noreply@swe-agent.ai>

skills/harness/hooks/harness-teammateidle.py

@@ -0,0 +1,160 @@
+#!/usr/bin/env python3
+"""Harness TeammateIdle hook — prevents teammates from going idle when
+harness tasks remain eligible for execution.
+
+Exit code 2 + stderr message keeps the teammate working.
+Exit code 0 allows the teammate to go idle.
+"""
+from __future__ import annotations
+
+import json
+import os
+import sys
+from pathlib import Path
+from typing import Any, Optional
+
+
+def _read_hook_payload() -> dict[str, Any]:
+    raw = sys.stdin.read()
+    if not raw.strip():
+        return {}
+    try:
+        data = json.loads(raw)
+        return data if isinstance(data, dict) else {}
+    except Exception:
+        return {}
+
+
+def _find_harness_root(payload: dict[str, Any]) -> Optional[Path]:
+    state_root = os.environ.get("HARNESS_STATE_ROOT")
+    if state_root:
+        p = Path(state_root)
+        if (p / "harness-tasks.json").is_file():
+            try:
+                return p.resolve()
+            except Exception:
+                return p
+    candidates: list[Path] = []
+    env_dir = os.environ.get("CLAUDE_PROJECT_DIR")
+    if env_dir:
+        candidates.append(Path(env_dir))
+    cwd = payload.get("cwd") or os.getcwd()
+    candidates.append(Path(cwd))
+    seen: set[str] = set()
+    for base in candidates:
+        try:
+            base = base.resolve()
+        except Exception:
+            continue
+        if str(base) in seen:
+            continue
+        seen.add(str(base))
+        for parent in [base, *list(base.parents)[:8]]:
+            if (parent / "harness-tasks.json").is_file():
+                return parent
+    return None
+
+
+def _load_json(path: Path) -> dict[str, Any]:
+    with path.open("r", encoding="utf-8") as f:
+        data = json.load(f)
+    if not isinstance(data, dict):
+        raise ValueError(f"{path.name} must be a JSON object")
+    return data
+
+
+def _priority_rank(v: Any) -> int:
+    return {"P0": 0, "P1": 1, "P2": 2}.get(str(v or ""), 9)
+
+
+def _is_harness_active(root: Path) -> bool:
+    """Check if harness skill is actively running (marker file exists)."""
+    return (root / ".harness-active").is_file()
+
+
+def main() -> int:
+    payload = _read_hook_payload()
+    root = _find_harness_root(payload)
+    if root is None:
+        return 0  # no harness project, allow idle
+
+    # Guard: only active when harness skill is triggered
+    if not _is_harness_active(root):
+        return 0
+
+    tasks_path = root / "harness-tasks.json"
+    try:
+        state = _load_json(tasks_path)
+        tasks_raw = state.get("tasks") or []
+        if not isinstance(tasks_raw, list):
+            return 0
+        tasks = [t for t in tasks_raw if isinstance(t, dict)]
+    except Exception:
+        return 0  # can't read state, allow idle
+
+    completed = {str(t.get("id", "")) for t in tasks if str(t.get("status", "")) == "completed"}
+
+    def deps_ok(t: dict[str, Any]) -> bool:
+        deps = t.get("depends_on") or []
+        if not isinstance(deps, list):
+            return False
+        return all(str(d) in completed for d in deps)
+
+    def attempts(t: dict[str, Any]) -> int:
+        try:
+            return int(t.get("attempts") or 0)
+        except Exception:
+            return 0
+
+    def max_attempts(t: dict[str, Any]) -> int:
+        try:
+            v = t.get("max_attempts")
+            return int(v) if v is not None else 3
+        except Exception:
+            return 3
+
+    pending = [t for t in tasks if str(t.get("status", "")) == "pending" and deps_ok(t)]
+    retryable = [
+        t for t in tasks
+        if str(t.get("status", "")) == "failed"
+        and attempts(t) < max_attempts(t)
+        and deps_ok(t)
+    ]
+    def key(t: dict[str, Any]) -> tuple[int, str]:
+        return (_priority_rank(t.get("priority")), str(t.get("id", "")))
+    pending.sort(key=key)
+    retryable.sort(key=key)
+    in_progress = [t for t in tasks if str(t.get("status", "")) == "in_progress"]
+
+    # Check if this teammate owns any in-progress tasks
+    worker_id = os.environ.get("HARNESS_WORKER_ID") or ""
+    teammate_name = payload.get("teammate_name", "")
+    owned = [
+        t for t in in_progress
+        if str(t.get("claimed_by") or "") in (worker_id, teammate_name)
+    ] if (worker_id or teammate_name) else []
+
+    if owned:
+        tid = str(owned[0].get("id") or "")
+        title = str(owned[0].get("title") or "")
+        sys.stderr.write(
+            f"HARNESS: 你仍有进行中的任务 [{tid}] {title}。"
+            "请继续执行或完成该任务后再停止。\n"
+        )
+        return 2  # block idle
+
+    if pending or retryable:
+        next_t = pending[0] if pending else retryable[0]
+        tid = str(next_t.get("id") or "")
+        title = str(next_t.get("title") or "")
+        sys.stderr.write(
+            f"HARNESS: 仍有 {len(pending)} 个待执行 + {len(retryable)} 个可重试任务。"
+            f"下一个: [{tid}] {title}。请继续执行。\n"
+        )
+        return 2  # block idle
+
+    return 0  # all done, allow idle
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())