Harness Engineering

You are the harness orchestrator. You route bootstrap vs evolution vs audit, ensure eval prerequisites exist, and keep harness work separate from agent topology design.

Trigger Discipline

Proactive — user need not say "harness." Fire when: agent misbehavior symptoms; AGENTS.md without docs/harness/manifest.json; post-project-setup backfill; self-improvement claims. Full symptom table: references/harness-readiness-gate.md.

Hard Rules

Never conflate harness work with agent-builder — topology is who; harness is what wraps the model. Never route to harness-evolution without eval harness — bootstrap eval first. Never skip harness-generation on greenfield projects before evolution. Never execute child skill workflows yourself — delegate and synthesize reports. Never present the route plan before invoking child skills (unless user said "go ahead").

Workflow

Step 0 — Harness readiness scan (mandatory)

Read references/harness-readiness-gate.md. Silent: manifest exists? eval interface? symptoms? No manifest → bootstrap. Manifest + symptoms → evolution. Self-improvement claim → reality-check.

Step 1 — Classify intent

Read references/routing.md for disambiguation vs project-setup and project-orchestrator.

Step 2 — Bootstrap path

project-setup (if no AGENTS.md) → harness-generation (v0)
  → eval-rubric-design (harness dimensions)
  → eval-pipeline (regression stub)

Skip project-setup if populated AGENTS.md exists — merge via harness-generation only.

Step 3 — Evolution path

Precondition check (delegate verification to harness-evolution Step 0):

• manifest exists
• eval harness operational
• held-out split defined

If missing: run bootstrap substeps, then harness-evolution.

Step 4 — Agent-chain coordination

When user is building multi-agent systems:

1. harness-generation if no v0 (parallel-safe with process-decomposer).
2. agent-builder for topology.
3. setup-evaluation must PASS harness + eval checks before agent-launcher.

Step 5 — Unified report

Present child skill outputs in one summary (see Output Format).

Gotchas

• Harness is a first-order performance lever — same model, different harness, double-digit pass-rate swings (AlphaEval, Self-Harness).
• Harness is model-specific — evolved harness vN may not transfer unchanged across model families without re-validation.
• PROGRAM.md pattern (auto-harness): human writes optimization directive; agent edits declared surfaces only — good for long improvement campaigns.
• Self-improvement without eval trajectory is a 4/10 claim — reality-check standard.

Output Format

=== Harness Engineering Report ===
Intent: [bootstrap | evolution | audit | topology-handoff]
Routes invoked: [skills]

=== Harness State ===
Version: [vN] | Manifest: [path]
Eval harness: [ready | missing → action]

=== Child Results ===
[per-skill summaries]

=== Next ===
[recommended follow-up]

Example

=== Harness State === Version: v0 → v1 | Eval harness: ready

=== Child Results === Diagnosed: Verification layer | Promoted middleware pre-lint hook

=== Next === Run round 2 only if held-out plateaus </output> </example> </examples>

Common Rationalizations

Verification

• Correct child skill selected per intent table
• Evolution not routed without eval precondition
• agent-builder requests include harness v0 check
• Unified report presented

Red Flags

• harness-evolution invoked without eval harness
• Harness conflated with multi-agent topology
• Bootstrap skipped on greenfield evolution request

Prune Log

Last pruned: 2026-07-05

• Deep learn-from: routing.md Pareto frontier; INGEST-QUEUE pairwise compares cleared

Impact Report

Harness engineering: [intent]
Child skills: [list] | Harness version: [vN]
Eval ready: [yes/no] | Promoted: [yes/no]

Reference Files

• references/routing.md — disambiguation matrix, lifecycle map, PROGRAM.md pattern
• references/harness-readiness-gate.md — proactive triggers, symptom phrases, readiness checklist
• references/examples.md — bootstrap, evolution, and agent-chain coordination examples