harness

name	harness
description	Guides the harness-engineering pipeline — turn a codebase into one that resists agentic slop with agent-neutral docs, mechanically enforced architecture, and three runtime guardrails

Harness Skill

Loaded by /supi:harness. Drives a six-phase pipeline that turns an arbitrary codebase into a harness-friendly one and installs a persistent anti-slop layer that catches the failure modes LLMs reliably fall into.

What it produces

• Tier 1 — agent-neutral: AGENTS.md, docs/architecture.md, docs/golden-principles.md, native lint/structural-test/eval configs at the repo root. Usable by any harness (Codex, Claude Code, Cursor, supipowers, …).
• Tier 2 — supipowers-aware: .omp/supipowers/config.json gate wiring + .omp/supipowers/review-agents/harness-architecture.md.
• Tier 3 — anti-slop: persistent slop queue, layer-aware context injection on every agent turn, pre-edit duplication probe, post-session dead-code sweep, lenient + strict scorecard, and architecture-aware LLM reviewer.

Phases

#	Phase	Artifact	Validator	Gate
1	Discover	<session>/discover.json	TypeBox schema + cross-check vs deps registry	user review
2	Research	<session>/research/<topic>.md	≥2 primary sources + ## Options / ## Recommendation	none
3	Design	<session>/design-spec.md + <session>/decisions.jsonl	Spec-reviewer sub-agent	user approval
4	Plan	~/.omp/supipowers/projects/<slug>/plans/<plan>.md	Reuses validatePlanMarkdown	OMP plan-mode UI
5	Implement	repo writes (Tier 1+2+3)	bun typecheck + bun test + anti-slop hooks loadable	none
6	Validate	<session>/validate-report.json	Re-runs every artifact + anti-slop scan + synthetic-edit test	user accept
—	GC	drift report + targeted fix sub-agents	reuses Validate	none

Each stage runs as a fresh platform.createAgentSession with a per-stage prompt. Stage runners are idempotent: if the canonical artifact exists and validates, the stage is skipped.

Gate modes

• default: gate at Discover review, Design approval, Plan-approval, Validate-accept.
• auto: end-to-end without user gates.
• manual: gate every stage.

Anti-slop guardrails

Three project-scoped runtime hooks, all individually toggle-able in .omp/supipowers/config.json:

{
  "harness": {
    "anti_slop": {
      "pre_edit_dupe_probe": { "enabled": true, "threshold": 0.85, "min_token_count": 30 },
      "post_session_sweep": { "enabled": true, "block_on_new_dead_code": false },
      "layer_context_inject": { "enabled": true, "addendum_max_chars": 800 },
      "score_floor": { "strict": 75, "lenient": 90, "release_blocking": false }
    }
  }
}

Hooks register only when .omp/supipowers/harness/marker.json exists at session start. Other repos see no behavior change.

Backend selection

Discover recommends a backend based on repo languages; Design lets the user override:

Repo profile	Recommended backend	Why
TypeScript / JavaScript only	fallow + supi-native	No Python dep, deepest supipowers integration
3+ languages, or Python/Rust/Go	desloppify	29-language coverage, battle-tested LLM review
TS-dominant + non-TS subtrees	hybrid	fallow on TS, desloppify on the rest
Niche / no external CLIs allowed	supi-native	Manual lint/dupe per stack

Score model

Scorecard has lenient + strict scores (0–100). Strict counts wontfix items as cost so it cannot be gamed. Score floor in config gates /supi:checks and CI when release_blocking: true.

Subcommands

• /supi:harness — bare entry. New repos start the pipeline; harness-installed repos prompt harden / rebuild / cancel.
• /supi:harness discover|research|design|plan-draft|implement|validate — run/advance one stage.
• /supi:harness resume — resume an in-flight session.
• /supi:harness status — display stage + score badge.
• /supi:harness gc — drain the slop queue, classify mechanical vs judgmental, and dispatch fix sub-agents.
• /supi:harness next — pop the next unresolved queue entry.
• /supi:harness resolve <id> — mark an entry resolved.
• /supi:harness backlog — list every open entry.
• /supi:harness score — recompute and display the score.
• /supi:harness pr-comment [--dry-run] [--pr=N] [--repo=owner/repo] [--session=<id>] [--mode=every-push|on-status-change] — render (or post) the sticky PR comment for the latest validate report. See docs/supipowers/harness/pr-comment.md.

Conventions you MUST follow

• Every phase persists a typed artifact before claiming done. Validate owns the completion claim.
• Re-running a phase is idempotent: unchanged inputs produce identical outputs.
• The slop queue is content-addressed; duplicate violations from different backends collapse to the same id.
• Hooks must complete in ≤500 ms p95. On timeout, emit a one-line warning and skip — never block on perf.
• Agent-neutral artifacts (Tier 1) MUST NOT depend on supipowers being installed.

When to run

• New repo: install the harness on day 0 so the anti-slop hooks observe every change.
• Existing repo: install after a major refactor so duplicates and dead code don't compound.
• Recurring: run /supi:harness gc weekly (or pin to CI) to drain the queue.