hatch3r-spec

hatch3r-spec is a command for Claude Code from hatch3r/hatch3r. It costs 63 tokens per session (4,522 once invoked), scanned A, original, MIT.

A command that determines whether a project is new or already has code, then creates the matching set of requirements and technical planning documents. Greenfield means a new project; brownfield means an existing project.

In plain words
What is it for?
Use it to produce requirements, acceptance criteria, risks, a test plan, and either early-stage product research or existing-code analysis and migration planning.
Why use it?
It removes the need to choose and coordinate separate specification workflows when the project’s starting state is unclear.

Command for Claude Code

Written for Claude Code: argument-hint in frontmatter. Also seen: mentions CLAUDE.md; mentions subagents; mentions AGENTS.md.

Part of the hatch3r plugin — 59 skills, 33 commands, 2 hooks shipped together

Good fit Use it to produce requirements, acceptance criteria, risks, a test plan, and…

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Install with agentmods
npx agentmods add commands/hatch3r/hatch3r/hatch3r-spec
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Clone the repo
git clone --depth 1 https://github.com/hatch3r/hatch3r

Made for: Claude Code.

Or install hatch3r, the plugin that ships this one along with the rest of its 59 skills, 33 commands, 2 hooks.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for hatch3r-spec

README.md
[![agentmods](https://agentmods.dev/badge/commands/hatch3r/hatch3r/hatch3r-spec.svg)](https://agentmods.dev/commands/hatch3r/hatch3r/hatch3r-spec)
Your own site
<a href="https://agentmods.dev/commands/hatch3r/hatch3r/hatch3r-spec"><img src="https://agentmods.dev/badge/commands/hatch3r/hatch3r/hatch3r-spec.svg" alt="Measured on agentmods" height="20"></a>
Per session 63 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 4,522 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00063 $0.04522
Opus 5 $0.00032 $0.02261
Sonnet 5 $0.00013 $0.00904
Haiku 4.5 $0.00006 $0.00452

Measured 3d ago against content hash c272d413552f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

hatch3r-spec scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

commands/hatch3r-spec.md · 239 lines

How it starts

The opening of the file, as written. The whole thing — 239 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/hatch3r-spec

Spec orchestrator that detects project state, picks the matching spec agent (hatch3r-greenfield-spec or hatch3r-brownfield-spec), and aggregates the per-state deliverable manifest — 8 deliverables greenfield, 9 brownfield: shared core (requirements, acceptance criteria, risk inventory, test plan) plus state-specific deliverables (greenfield: market/competitive/persona/tech-stack; brownfield: codebase-map/pattern-detection/integration/migration/non-destructive-check). The Deliverable Manifest below is the single source of truth for filenames and output location; both agents mirror it. Routing is mutually exclusive — exactly one spec agent runs per invocation.

Relationship to /hatch3r-project-spec

/hatch3r-spec and /hatch3r-project-spec are both greenfield entry points and overlap on business research (market, competitive analysis, personas). They are meant to run in sequence, not in parallel:

  • This command produces the PRD (docs/specs/prd.md) plus market/competitive/persona/tech-stack research — the product-requirements layer.
  • /hatch3r-project-spec produces the technical-design tree (ADRs, domain model, per-module specs, todo.md, AGENTS.md) plus business-doc specs — the layer that consumes the PRD.

Sequence: run /hatch3r-spec first, then hand its docs/specs/ output to /hatch3r-project-spec. project-spec's Step 1 extracts vision, personas, and market context from the PRD instead of re-interviewing, and skips regenerating the market/competitive research this command already wrote. Running both from scratch re-executes the overlapping business-research fan-out and yields two unreconciled spec trees — sequence them to avoid it.

Deliverable Manifest (single source of truth)

This table is the one authoritative contract for what a spec run writes — filename, output location, and count. Both spec agents (hatch3r-greenfield-spec, hatch3r-brownfield-spec) mirror these filenames and write to the passed output_root; where an agent and this table disagree, this table wins. Agents cite this manifest rather than restating a divergent contract.

Read the full file on GitHub · 239 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 239 lines · 63 tokens per session scan A c272d413552f

Subscribe to this mod's changes

hatch3r-spec is a command published in the GitHub repository hatch3r/hatch3r (26 stars, last pushed 2d ago), licensed MIT. It adds 63 tokens to every session and 4,522 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.