chug-cli 0.1.2

Agent-first changelog management for teams

Chug

Keeping CHANGELOG.md tidy on a team is one of those things that's never quite as simple as it should be. Chug is a small tool I built to take the friction out of it. It works well for me, so I'm sharing it.

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The Problems

Parallel branches create merge conflicts. Every PR that edits CHANGELOG.md touches the same file at the same position. On an active team this produces conflicts regularly.

Release mechanics are manual. The typical pattern is an "Unreleased" section at the top that accumulates changes and gets renamed to a version when you ship. It works, but it's a manual step that's easy to skip or do inconsistently.

Agents don't know the rules. When you ask an agent to open a pull request, it has no idea a changelog entry is expected. It ships the PR without one unless it's been explicitly taught otherwise.

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How Chug Fixes It

Instead of editing CHANGELOG.md directly, each change gets written as a small YAML file in a changes/ directory. Branches create new files — they don't edit existing ones. New files never conflict with each other.

changes/
  2024-01-15T143022-fix-session-timeout.yml
  2024-01-16T091345-add-export-endpoint.yml
  2024-01-17T162801-update-rate-limits.yml

At release time, one command rolls all pending files into a new versioned section in CHANGELOG.md and deletes them.

Chug ships three things to make this work end-to-end:

• A CLI for creating change YAML files. Automatically pulls author info from your git config and validates that the change is categorized into one of your configured categories.
• A GitHub Action that installs the chug CLI in CI. Use it in validate and release workflows via shell steps.
• An agent skill so agents know to create a change file when they open a PR.

That's it. Chug is deliberately small. It's not a release platform or a versioning system — just a better way to maintain your changelog.

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Quick Start

Install:

uv tool install chug-cli
# or
pipx install chug-cli

Bootstrap a repo:

chug init

Creates chug.config.yml, a changes/ directory, and a CHANGELOG.md with an insertion marker — without touching anything that already exists.

Record a change:

chug new --description "Fix session timeout on mobile" --category bug

Writes a timestamped YAML file into changes/. No edit to CHANGELOG.md. No coordination required. Safe to run on any branch.

Preview before releasing:

chug preview

Renders the full release output without touching any files.

Cut a release:

chug release --version 1.4.0

Inserts a new versioned section at the configured marker in CHANGELOG.md, then deletes the processed change files.

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Change File Format

description: Fix session timeout on mobile
category: bug
stories:
  - sc-12345
authors:
  - name: Jane Doe
    github: janedoe

description and category are required. stories and authors are optional. Chug populates authors from your local git config when it can; if it can't, it writes authors: [] rather than failing.

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Author Detection

When you run chug new, Chug automatically populates the authors field by reading two git config values:

• user.name — your display name
• github.user — your GitHub username

If both are set, the entry looks like:

authors:
  - name: Jane Doe
    github: janedoe

If neither is set, authors is written as an empty list and Chug continues without failing.

To set these up:

git config --global user.name "Jane Doe"
git config --global github.user janedoe

user.name is typically set already. github.user is not a standard git config key — you need to add it explicitly if you want GitHub usernames in your changelog entries.

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Configuration

chug.config.yml lives at the repo root:

changelog_file: CHANGELOG.md
categories:
  - feature
  - chore
  - bug
story_format: "{id}"
story_link_template: "https://your-tracker.com/stories/{id}"
git_base_branch: main

changelog_style — guidance for agents

An optional field that documents how your team wants entries written. It has no effect on CLI behavior — it exists as structured guidance for agents and automation that create change files on your behalf.

changelog_style: |
  Write descriptions from the user's perspective, not the implementer's.
  Be specific about what changed and why it matters.
  Keep descriptions under 100 characters.
  Good: "Fix crash when opening documents with special characters in the filename"
  Avoid: "Handle edge case in path parsing logic"

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GitHub PR Links

With a GitHub token, Chug enriches each changelog entry with a link to the pull request that introduced the change file:

- Fix session timeout on mobile ([#87](https://github.com/owner/repo/pull/87), [Jane Doe](https://github.com/janedoe))

Without a token, entries render without PR links and everything else works the same.

export GITHUB_TOKEN=ghp_...
chug release --version 1.4.0

Chug finds the most recent base-branch commit that touched the change file, looks up associated pull requests, and adds the link. All API calls are read-only.

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GitHub Actions

A single setup action installs the chug CLI in your workflow. Then call CLI commands in shell steps.

- uses: crayment/chug@v1

Validate workflow

chug validate checks that the current PR added or modified a file in changes/. It diffs against the base branch using GITHUB_BASE_REF in CI, or falls back to git_base_branch from your config when run locally. On failure in CI, it emits a GitHub Actions error annotation.

name: Validate Changelog Entry

on:
  pull_request:

permissions:
  contents: read
  pull-requests: read

jobs:
  validate:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      - uses: crayment/chug@v1
      - run: chug validate

Release workflow

chug release writes the versioned changelog section and deletes the processed change files. Committing and pushing is left to the workflow.

name: Update Changelog

on:
  workflow_dispatch:
    inputs:
      version:
        required: true

permissions:
  contents: write
  pull-requests: read

jobs:
  release:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
      - uses: crayment/chug@v1
      - run: chug release --version ${{ inputs.version }}
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      - name: Commit and push changelog
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
          git add CHANGELOG.md
          git add -A changes/ || true
          git diff --cached --quiet || git commit -m "Update changelog for ${{ inputs.version }}"
          git push

Push is left to the calling workflow intentionally — whether it succeeds depends on your branch protection rules and token permissions.

Setup action inputs

Input	Description
version	Version of the chug CLI to install. Defaults to the latest release.
source	Where to install from. Defaults to PyPI. Primarily used for pre-release testing.

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Agent Skill

Chug ships a companion skill that teaches agents how to use the CLI, what makes a good changelog entry, and how to apply your project's changelog_style guidance. Once installed, agents working in your repository create change files instead of editing CHANGELOG.md directly.

npx skills add crayment/chug

The skill is a single SKILL.md file. Copy it, adjust the guidelines to match your team's voice, and host it wherever you want.

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License

MIT