3Powers

The spec is the law. Agents execute. An independent judiciary determines whether the implementation complies with the spec.

3Powers is a portable, open agent harness with a judiciary — it drives your coding agents through the whole agentic lifecycle at high autonomy, then does the one thing a bare harness never does: it refuses to take their word for it. Agents do the building. An independent judiciary — an oracle that never saw the code, a deterministic gate suite, and a signed, tamper-evident ledger — proves that what shipped matches the spec you approved.

This package (3powers on PyPI) provides the 3pwr command: the native provider-agnostic executive, the deterministic gate runner, the oracle-independence checks, and the hash-chained, Ed25519-signed verdict ledger you can verify offline. It is model-, language-, and provider-agnostic, uses Git as its substrate, and needs no CI/CD platform.

Install

Install with uv — the package is published as 3powers, and the command it installs is 3pwr:

uv tool install 3powers        # installs the `3pwr` command

Or run it once without installing:

uvx 3powers --help

Python 3.11+ is required.

Quickstart: the autonomous path

# 1. In YOUR project (new or existing), run the guided onboarding. It asks for the language,
#    where to keep the signing key (always OUTSIDE the repo), and your default autonomy mode.
cd /path/to/your/project && 3pwr init

# 2. Describe what you want built, and let the lifecycle run:
3pwr run "add rate limiting to the login endpoint" --mode auto

3pwr run streams a live stage tracker and in auto mode stops only at the two human gates: approving the spec, and the final sign-off. Every step lands in the signed, offline-verifiable ledger, so a run is resumable and auditable.

The deterministic gates, ledger, and enforcement are pure 3pwr and need no agent at all — the gates-only path works fully offline. Every run emits one normalized verdict a human can read without opening a single agent transcript:

verdict FAIL  spec=VUTIL tier=Standard adapter=typescript
  ✓ format · biome          ✓ lint · biome        ✓ types · tsc
  ✓ tests · vitest          ✓ diff_coverage · 3pwr-covdiff  (100.0% ≥ 80.0%)
  ✗ dependency_scan · osv-scanner
      - GHSA-4x5r-pxfx-6jf8 in @babel/core
  ✓ secret_scan             ✓ gate_gaming         ✓ spec_conformance  (5 requirements traced)
  failures:
    • vulnerable_dependency: GHSA-4x5r-pxfx-6jf8 in @babel/core
  ↳ ledger entry #0 signed by ed25519:4fd71c543b0f499c

Why: when one model does everything, validation is a mirror

Hand a capable agent a feature and it will happily write the spec, the code, the tests, and the review. They all agree, because they all came from the same mind. A passing build only proves the model agreed with itself. 3Powers calls this the separation-of-powers collapse, and restores three independent branches:

• ⚖️ Legislative — the spec is the law. Versioned, testable requirements every later stage answers to.
• 🛠️ Executive — agents build against it. They may write their own tests, but those never replace the independent check.
• 👩‍⚖️ Judicial — an independent judiciary decides. An oracle authored from the spec by a different model family, a deterministic gate suite, and a human sign-off.

The lifecycle runs in eight stages — Discovery → Spec → Plan → Build → Verify → Review → Ship → Observe — with a signed, hash-chained ledger recording every verdict and sign-off so the whole run is verifiable offline.

Documentation

Full guides live in the repository:

• Getting Started — prerequisites, install, and the whole thing end-to-end.
• Concepts — the three powers, the lifecycle, risk tiers, oracle independence, the trust spine.
• CLI Reference — every 3pwr command and flag.
• Engine Architecture — the gates, the verdict, and the ledger.
• Glossary — every term of art, defined once.
• STATUS — implementation status, validated against the spec.

Repository: https://github.com/VerzCar/3powers

Contributing

Working on the engine itself? See CONTRIBUTING.md for the dev environment and the checks it must always pass (ruff + mypy + pytest, plus the engine gating its own code at the strictest tier).

License

Apache-2.0.