Harness Contract and Lifecycle

Harness Contract and Lifecycle

Fact-check status

Reviewed claim by claim on 2026-09-02 against the primary or official sources identified inline as S1 and S2. Recommendations are design guidance unless a cited standard makes them normative.

Key jargon

Term Plain-language meaning
Contract An explicit agreement about inputs, outputs, errors, permissions, and invariants. S1
Lifecycle The stages from request admission through completion, cancellation, or recovery. S1
Invariant A condition that must remain true at every relevant stage. S1
Version pin A recorded dependency, prompt, model, schema, or policy version used for a run. S1

Key concepts

Concept map

flowchart LR
    A["Admit validated request"] --> B["Execute versioned lifecycle"]
    B --> C["Enforce invariants"]
    C --> D["Close with result and evidence"]

Diagram semantics verified against S1 and S2 on 2026-09-02.

Lifecycle

  1. Scope: user, task, harm, data, action, and stop boundaries. S1
  2. Baseline: representative examples and current non-AI performance. S1
  3. Prototype: smallest prompt/model/workflow that can test value. S1
  4. Evaluate: quality, safety, latency, cost, and subgroup behavior. S1
  5. Harden: permissions, isolation, validation, recovery, and logging. S1
  6. Pilot: limited users/data/actions with rollback. S1
  7. Operate: monitoring, incidents, versioning, and human escalation. S1
  8. Change: regression gates for model, prompt, tool, retrieval, or policy. S1
  9. Retire: revoke access, handle memory/data, preserve required evidence. S1

Harness contract

Write down purpose, non-goals, owner, users, data classes, models, tools, memory, action inventory, evaluation suite, budgets, approval gates, incident owner, retention, and retirement trigger. S1

Definition of done

A demo that produces a good answer is not production readiness. Done means the system meets a documented contract on representative tests and fails within known boundaries. S1

Dumpster-derived lesson

The local research repeatedly supports artifact-backed, stage-level evaluation: fluent final output must not substitute for trace, state, or effect evidence. S1