feature-marker - Skill-first feature workflow for Claude, Codex, and Gemini

feature-marker is a portable LLM skill for turning one feature request into a clear flow: PRD, TechSpec, Tasks, implementation, verification, local commit, and branch handoff.

The npm package is only an installer for skill files. It does not run the workflow, own feature state, push branches, or open pull requests.

Why Star This Repo

• Works where you already code: Claude, Codex, and Gemini.
• Keeps the workflow simple: install once, then invoke the skill from a prompt.
• Produces plain repo artifacts your team can review and keep.
• Adds an implementation grill before coding so weak specs, missing tests, and handoff gaps are found early.
• Stops at a clean local branch handoff. You stay in control of push and PR creation.

Quick Start

Install the skill files:

npx -y @viniciuscarvalho/feature-marker install --runtime all

Open any git project in Claude, Codex, or Gemini and ask:

Use feature-marker to implement my-feature.

feature-marker will create or reuse:

tasks/my-feature/prd.md
tasks/my-feature/techspec.md
tasks/my-feature/tasks.md

Then it works through the feature, verifies it, commits locally, and prints the exact commands you can run to push and open a PR.

Install

Use npx when you want the latest npm installer without a global install.

Install only Claude:

npx -y @viniciuscarvalho/feature-marker install --runtime claude

Install the skill into all supported runtimes:

npx -y @viniciuscarvalho/feature-marker install --runtime all

Install only one runtime:

npx -y @viniciuscarvalho/feature-marker install --runtime codex
npx -y @viniciuscarvalho/feature-marker install --runtime gemini

Use --dry-run to preview install targets:

npx -y @viniciuscarvalho/feature-marker install --runtime all --dry-run

Global npm install is optional and only shortens the command:

npm install -g @viniciuscarvalho/feature-marker
feature-marker install --runtime codex

Homebrew is also supported on macOS/Linux:

brew tap viniciuscarvalho/tap
brew install feature-marker
feature-marker install --runtime all

Use In Your LLM

After installation, open any git project in Claude, Codex, or Gemini and invoke the skill from the prompt. Interactive mode is not required and is not the v1 path.

Claude prompt:

Use feature-marker to implement billing-observability.

Codex or Gemini prompt:

Use feature-marker to plan and implement billing-observability.

Use feature-marker in tasks-only mode for billing-observability.

Use feature-marker to create only the PRD for import-csv.

The skill reads the repository, creates or uses artifacts under tasks/{slug}/, runs through PRD -> TechSpec -> Tasks -> implementation grill -> implementation -> verification, commits locally, and prints exact push/PR handoff commands. The grill pass finds gaps before coding; it asks the user only when a finding changes scope or requires a product decision.

PRD, TechSpec, and Tasks are created from bundled templates installed with the skill. The agent fills {slug} and {feature_title} and writes: tasks/{slug}/prd.md, tasks/{slug}/techspec.md, and tasks/{slug}/tasks.md.

How It Works

The published package contains a small installer CLI and the skill files. The code path is intentionally narrow:

1. feature-marker install --runtime ... resolves the package root and the user's home directory.
2. It copies the selected runtime skill to its native skill folder.
3. It copies the shared PRD, TechSpec, and Tasks templates into that install.
4. For Claude, it also installs the companion agent wrapper.
5. The actual feature workflow runs later inside Claude, Codex, or Gemini when the user asks to use feature-marker.

The CLI does not implement the feature workflow. Commands such as run, resume, status, and capabilities intentionally fail with guidance to invoke the installed skill from the LLM prompt.

Installer Commands

Workflow commands such as run, resume, status, and capabilities are not supported. Invoke feature-marker inside your LLM instead.

Workflow Contract

feature-marker keeps user-facing state in plain artifacts:

tasks/{slug}/
  prd.md
  techspec.md
  tasks.md

The skill is branch-first:

• Create or require a feature branch before implementation.
• Use a worktree only when the current checkout is dirty or the user asks.
• Continue from PRD to TechSpec to Tasks to an implementation grill by default.
• Resolve grill findings in the artifacts before coding.
• Stop only for true ambiguity, unrelated dirty work, or blocked verification.
• Preserve unrelated local changes.
• Finish with a local commit and exact handoff commands.
• Do not push or open a PR automatically.

Example handoff:

git push -u origin feature-marker/billing-observability
gh pr create --base main --head feature-marker/billing-observability

Prompt Intents

There are no CLI workflow modes. Use these words in your LLM prompt when useful:

spec-driven and ralph-loop are out of scope for this skill-first v1 unless they are rebuilt as explicit skill instructions.

Runtime Install Targets

• Claude: ~/.claude/skills/feature-marker and ~/.claude/agents/feature-marker.md
• Codex: ~/.codex/skills/feature-marker
• Gemini: ~/.gemini/skills/feature-marker

Verification

Run the deterministic suite:

npm test

Package smoke:

npm pack --dry-run --json

Learn More

• Distribution notes: feature-marker-dist/README.md
• Project context: CONTEXT.md
• Architecture decision: docs/adr/012-skill-first-workflow.md

License

MIT