Harness Engineering

Harness Engineering

Overview

Turn repository documentation into a maintained system of record for agents. Keep AGENTS.md short, store durable knowledge in versioned Markdown, and remove stale docs instead of preserving legacy navigation.

Required Outcome

Leave the target repository with:

• a short AGENTS.md that acts as a table of contents
• a top-level ARCHITECTURE.md
• a structured docs/ knowledge store
• explicit treatment of doc drift in docs/QUALITY_SCORE.md and docs/exec-plans/tech-debt-tracker.md
• a passing run of scripts/validate_harness_docs.py

Workflow Selection

Choose one of two flows:

1. Bootstrap

• Use for a new repository or one with little or no durable documentation.
• Copy the always-required templates first, then add only the conditional templates that match the real repo surface.

2. Migration

• Use for an existing repository with docs that may be stale, duplicated, or scattered.
• Inventory current docs against code, configs, schemas, tests, and runtime entrypoints before writing anything.

Read these references before executing:

• references/knowledge-store-contract.md
• references/document-contracts.md
• references/bootstrap-playbook.md or references/migration-playbook.md
• references/harness-engineering-article.md when you need the rationale behind a rule

Bootstrap Flow

1. Inspect the real repository surface.

• Identify runtime entrypoints, package managers, app domains, UI surfaces, API surfaces, data stores, and any product-spec or design-doc needs.
• Do not create conditional docs unless the repo actually has that surface.

2. Copy the always-required templates from assets/templates/always/.

• Materialize AGENTS.md, ARCHITECTURE.md, docs/PLANS.md, docs/QUALITY_SCORE.md, docs/RELIABILITY.md, docs/SECURITY.md, docs/references/index.md, and docs/exec-plans/.

3. Copy only matching conditional templates from assets/templates/conditional/.

• design-docs/ when the repo needs durable design rationale.
• product-specs/ when the repo has user-facing features or workflow specs.
• DESIGN.md when visual or interaction rules matter.
• FRONTEND.md when there is a browser, desktop, or app UI surface.
• PRODUCT_SENSE.md when product tradeoffs should be encoded for agents.
• generated/db-schema.md when the repo owns a database schema or migrations.

4. Rewrite template placeholders so they describe the actual repository.

• Replace generic text with real domains, components, constraints, and commands.
• Update AGENTS.md so it links to every required doc and every conditional doc that now exists.

5. Seed continuous maintenance.

• Add initial grades and gaps to docs/QUALITY_SCORE.md.
• Add follow-up doc debt items to docs/exec-plans/tech-debt-tracker.md.

6. Validate mechanically.

• Run python3 <skill-dir>/scripts/validate_harness_docs.py <target-repo>.
• Fix findings before claiming the setup is complete.

Migration Flow

1. Build a doc inventory before editing.

• Find all repository docs that influence implementation, onboarding, architecture, specs, and runbooks.
• Compare each doc to code, config, schemas, migrations, tests, and current entrypoints.

2. Classify every doc using exactly one status:

• keep-and-move: still true, but needs relocation into the new structure
• rewrite: topic is still needed, but content is materially wrong or underspecified
• replace: existing doc shape is counterproductive; create a fresh document with the same responsibility
• delete: obsolete, misleading, duplicated, or no longer justified

3. Rewrite the knowledge store around current truth.

• Create the required harness structure.
• Move or rewrite surviving documents into the contract layout.
• Remove stale docs from active navigation immediately. Do not leave compatibility breadcrumbs to misleading content.

4. Rebuild navigation.

• Keep AGENTS.md short and link only to living sources of truth.
• Update directory indexes so they cover all sibling docs and do not point at deleted files.

5. Record debt and freshness.

• Add any remaining doc gaps to docs/QUALITY_SCORE.md.
• Add concrete cleanup items to docs/exec-plans/tech-debt-tracker.md.

6. Validate mechanically.

• Run the validator and clear every finding.

Execution Rules

Enforce these rules in both flows:

• Prefer repository truth over prior documentation.
• Delete or replace stale docs instead of preserving backward compatibility.
• Keep knowledge in-repo and versioned; if an agent cannot discover it in the repo, treat it as missing.
• Encode invariants as structure, links, and checks instead of long prose.
• Keep AGENTS.md as a map, not an encyclopedia.

Resource Map

• references/harness-engineering-article.md: section-by-section paraphrase of the OpenAI article and the rationale behind the workflow.
• references/knowledge-store-contract.md: required layout, navigation rules, and conditional surfaces.
• references/document-contracts.md: what each target doc must contain and when to omit it.
• references/bootstrap-playbook.md: ordered instructions for greenfield setup.
• references/migration-playbook.md: ordered instructions for audit, rewrite, and retirement.
• assets/templates/always/: base templates that every harness-style repo should start with.
• assets/templates/conditional/: optional templates that are copied only when the repo needs them.
• scripts/validate_harness_docs.py: mechanical validator for topology, links, index freshness, and AGENTS.md mapping drift.

Source: JacobLinCool/harness-engineering-skill — distributed by TomeVault.