Greenfield

Reverse engineer clean behavioral specs from any codebase.

Greenfield reads source code, documentation, SDKs, runtime behavior, and binaries, then produces behavioral specifications, test vectors, acceptance criteria, and a full provenance trail. The output describes what the software does — not how any particular codebase does it — so a fresh implementation team can build against the specs without inheriting the original's internal structure.

Greenfield is a Claude Code plugin. It runs inside the claude CLI and uses Claude agents as the workers that read code, write specs, and audit output.

Installation

/plugin marketplace add prime-radiant-inc/prime-radiant-marketplace
/plugin install greenfield@prime-radiant-marketplace

Restart Claude Code after installing.

Usage

Extract specs

claude
> /analyze /path/to/target

/analyze runs a seven-layer pipeline. It discovers the available intelligence sources (source, docs, SDK, community, runtime, binary, git history, tests, UI, contracts), gathers evidence from each, synthesizes behavioral specs with provenance citations, generates test vectors and acceptance criteria, sanitizes the specs of implementation details, then runs a second-pass review of the result.

Target shape doesn't matter. Greenfield has been used on single-file minified JavaScript bundles and on source-tree projects; the pipeline also has a path for decompiled native binaries. The methodology adapts to what's there.

Workspace output:

workspace/
├── raw/         # Analysis artifacts with source references
├── output/      # Sanitized specs for the implementation team
│   ├── specs/
│   ├── test-vectors/
│   └── validation/
└── provenance/  # Citation audit trail

Re-sanitize an existing workspace

claude
> /sanitize /path/to/workspace

Re-runs the sanitization pass on an existing workspace. Useful when the initial pass left contamination that the audit caught.

Implement from the output specs

Greenfield stops at the specs. The implementation team reads workspace/output/ and builds against the behavioral specs, test vectors, and acceptance criteria there.

How it works

The pipeline dispatches agents with role-specific prompts across the seven layers. Each dispatch runs one of two generic agent types loaded with a specific skill:

• analyzer — the workhorse. Reads evidence and writes specs. Dispatched under many roles across layers: discovery-agent, bundle-splitter, chunk-analyzer, function-analyzer, doc-researcher, community-analyst, sdk-analyzer, cli-explorer, behavior-observer, feature-discoverer, architecture-analyst, api-extractor, synthesizer, module-mapper, deep-dive-analyzer, behavior-documenter, user-journey-analyzer, contract-extractor, spec-verifier, source-completeness-checker, test-vector-generator, test-generator, acceptance-criteria-writer, spec-reviewer, structural-leakage-reviewer, content-contamination-reviewer, behavioral-completeness-reviewer, deep-read-auditor, fidelity-validator.
• sanitizer — rewrites raw specs into output specs free of implementation details. Dispatched during Layer 5 and for remediation during Layers 6 and 7.

Pipeline

Layer	Roles	Output
L1: Intelligence	bundle-splitter, chunk-analyzer, function-analyzer, doc-researcher, community-analyst, sdk-analyzer, cli-explorer, behavior-observer	Raw evidence from source, docs, SDK, community, runtime, binary
L2: Synthesis	feature-discoverer, architecture-analyst, api-extractor, synthesizer, module-mapper	Feature inventory, architecture model, module map
L3: Deep Docs	deep-dive-analyzer, behavior-documenter, user-journey-analyzer, contract-extractor	Behavioral specs, journeys, contracts
Gate 1	spec-verifier	Correctness, contradictions, gaps
Gate 1b	source-completeness-checker	Every user-facing surface captured
L4: Validation	test-vector-generator, test-generator, acceptance-criteria-writer	Test vectors, test specs, acceptance criteria
Gate 2	spec-reviewer	Implementation leakage, completeness, quality
L5: Sanitization	sanitizer	Output specs rewritten from understanding, not copied
L6: Review	structural, content, completeness reviewers + deep-read auditors	Second-pass contamination review
L7: Fidelity	fidelity-validators	Flags behavioral detail lost or weakened during sanitization

License

Apache 2.0. Copyright 2026 Prime Radiant, Inc.