Claude Harness
The .claude/ harness controls and validates agent-assisted development. The
live machine-generated inventory is Harness Index.
Executable components
| Area | Contents |
|---|---|
| Rules | Engineering, security, testing, and response constraints |
| Skills | On-demand project workflows |
| Agents | Named specialists with bounded ownership and tools |
| Memory | Shared project facts, handoff contract, and per-agent learned memory |
| State | Gitignored session, compaction, active-agent, and handoff records |
| Commands | Harness audit, status, handoff, sync, and pre-commit gates |
Named agents
| Agent | Responsibility |
|---|---|
harness-governor |
Hooks, sync, state contracts, and harness integrity |
memory-state-reviewer |
ADK session, memory, compaction, and A2A boundaries |
security-reviewer |
Read-only data-leak and callback boundary review |
verification-runner |
Deterministic gates and reproducible failure reports |
Each profile uses project-scoped persistent memory and writes a sanitized handoff before returning control.
Lifecycle hooks
| Hook | Script | Purpose |
|---|---|---|
SessionStart |
scripts/harness_runtime.py |
Initializes/resumes state and injects durable project memory |
PreToolUse (matcher *) |
scripts/check_harness.py |
Verifies profiles, memory, hook wiring, indexes, and mirror integrity |
PreCompact |
scripts/harness_runtime.py |
Snapshots local state before context compaction |
SubagentStart |
scripts/harness_runtime.py |
Registers ownership and injects pending handoffs |
SubagentStop |
scripts/harness_runtime.py |
Records completion and a sanitized fallback handoff |
Stop |
scripts/harness_runtime.py |
Checkpoints turn state, then runs wiki/harness sync |
SessionEnd |
scripts/harness_runtime.py |
Marks session ended without deleting recovery state |
Scripts
harness_runtime.py— standard-library lifecycle state, context injection, compaction snapshots, and handoff queue.check_harness.py— fails fast on missing executable contracts, invalid hook wiring/frontmatter, unindexed files, or mirror drift.sync_harness.py— incrementally mirrors managed.claude/files and preserves destination-only.agents/skills/assets.sync_wiki.py— regenerates machine-owned wiki content and calls safe mirror synchronization.
Memory ownership
| File | Contains |
|---|---|
MEMORY.md |
Generated workspace inventory |
.claude/memory/project.md |
Shared durable facts injected at lifecycle boundaries |
.claude/memory/handoff-protocol.md |
Cross-agent completion contract |
.claude/agent-memory/<agent>/MEMORY.md |
Project-scoped learned memory |
.claude/state/ |
Gitignored ephemeral lifecycle and handoff state |
Related: Development Workflow · Testing and Eval