agent-harness

name	agent-harness
description	Use when user says “你是主 agent”, “写一个 harness” / “write a harness”, multi-agent delegation, parallel workers, durable handoff, cross-model continuation, resumable execution, or protected evidence-based acceptance. Explicit requests compile intent before choosing Native, Portable, or Audited; ordinary implementation, planning, and testing do not trigger this skill.

Agent Harness

Add only controls missing from the runtime. “写一个 harness” first turns user intent into a reviewable contract; it does not itself create .harness artifacts, select Audited, or dispatch a worker.

Intent-to-Contract Gate

For an explicit harness request, read references/spec-synthesis.md and run its synthesis protocol before the Mode Gate or any dispatch, even with a measurable plan. Produce a user-reviewable alignment packet and contract; for non-implementation work, return them and stop. The contract names:

• user-facing and system outcomes, observable done_when, and explicit success_not;
• allowed scope, ownership, non-goals, compatibility, constraints, relevant edge/failure handling, and approval boundaries;
• evidence plus a decidable pass algorithm for every acceptance criterion;
• fact, assumption, recommended_default, and open_decision labels.

Use recommended_default only for low-risk, reversible gaps. A material choice, conflict, missing owner/capability, public-contract change, security/privacy issue, cost, irreversible behavior, or approval need is an open_decision: expose it and do not dispatch. The packet precedes the first worker and includes false-success signals, phase map, and the first narrow task.

Dispatch Readiness

Dispatch only after outcome, system completion, done_when, success_not, scope, ownership, non-goals, constraints, edge/failure handling, approvals, evidence/pass algorithms, and defaults are explicit with no material open decision. The first task needs one responsibility, dependencies, bounded inputs/outputs, allowed scope, execution guidance, verification gate, decidable PASS, and Stop rule. Write one runtime plan; track worker status and evidence.

Workflow Composition

For code changes, use the repository's established coding workflow or an available matching coding skill. This skill does not replace, copy, or weaken it; do not require a particular companion skill by name.

Mode Gate

Choose once after synthesis:

Mode	Use when	Durable state
Native	Session can implement and verify the slice.	None; use the runtime Plan
Portable	Work crosses a session/model boundary, external wait, or context loss.	.harness/<slug>/contract.json, events.jsonl, capsule.md
Audited	Protected/disputed transition needs typed proof.	Only justified witness, receipts, fencing, trace, and registry controls

Mode controls persistence and evidence depth; synthesis is orthogonal. If Native fits, do not load references, create harness files, or add audit controls solely because this skill triggered.

Execution Shape

Delegation is independent of mode. V3 micro work may stay on the parent/main route only after explicit scope-local, low-risk/no-protected-boundary, context-complete, short-verification, and delegation-cost-higher confirmations. Explicit user delegation overrides the micro direct route. Ordinary or execution-heavy work uses one bounded worker; complex work uses parallel workers only at independent modules or ownership boundaries; coupled writes stay serial or with one owner. Try another verifiable bounded worker first; if none exists or resolution fails, block. Parent direct fallback requires explicit user authorization. Workers do not redefine the contract; they do not recursively delegate. Keep requested and resolved models separate; only runtime evidence establishes the route.

The main agent owns goal, contract, plan, dispatch, status, integration, and acceptance. Each worker gets a self-contained packet with constraints, edge cases, evidence requirements, PASS, and Stop; it returns actual changed paths, verification output and exit status, unverified paths, assumptions, and blockers. A worker report or PASS never establishes completion; the parent inspects actual diff and decisive evidence.

Progress Circuit Breaker

Progress is new evidence, an artifact change, a test result, or a binding decision advancing a named done_when criterion or named critical-path blocker. Generated metadata, reports, package rebuilds are activity that does not count as progress. After two consecutive no-progress cycles, run the cheapest falsifying experiment; if it yields no evidence, stop and report STALLED. This policy must not increase reasoning effort because work stalled.

Durable And Audited Work

Materialize Portable state only after an actionable plan and durability trigger; read references/portable-contract.md before materialize, handoff, resume, or close. Preserve legacy handoff-v1/Full reads and resumability. For Audited work, read references/harness-protocol.md and one control reference; add only justified protected controls. Persist observable facts, never hidden reasoning, chats, secrets, or provider sessions.

Load On Demand

Use references/proportionality.md for mode/stall decisions, references/public-contracts.md for public JSON/CLI contracts, references/state-witness.md for stateful behavior, references/tdd-gates.md for protected chronology, references/stop-conditions.md for detailed stops, and references/model-routing.md plus the adapter for optional routing.

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Agent Harness v10.0.0 | 2026-08-27