caveman-commit Skill Use Cases: Automating Conventional Commits in JuliusBrussee/caveman

The caveman-commit skill generates strict Conventional Commit messages from staged changes without executing any Git commands, making it ideal for standardizing team workflows, rapid drafting, and CI/CD automation.

The caveman-commit skill in the JuliusBrussee/caveman repository provides an LLM-driven utility for creating standardized commit messages. Unlike traditional Git hooks, this skill outputs formatted text without staging, committing, or modifying repository state, allowing developers to maintain consistent Conventional Commits across any workflow.

How the caveman-commit Skill Works

Rule-Based Message Generation

According to the source code in skills/caveman-commit/SKILL.md, the skill enforces a strict rule-set that governs how the LLM constructs messages. Lines 14-20 mandate the subject line format <type>(<scope>): <imperative summary> with a hard 50-character limit (absolute maximum 72) and no trailing periods. Lines 22-27 specify that the body section appears only when the reasoning behind changes isn't obvious, such as for breaking changes, migrations, security fixes, or linked issues. Lines 29-34 explicitly prohibit AI attribution, filler phrases like "this commit does X", emojis, and restating filenames.

Command Interface

The skill registers itself as a CLI command through commands/caveman-commit.md, enabling explicit invocation via /caveman-commit or natural language triggers. Because the implementation outputs only text (as noted in line 65 of SKILL.md), it integrates safely into existing tooling without side effects.

Core Use Cases for the caveman-commit Skill

Standardizing Commit Messages Across Teams

Teams requiring Conventional Commits can invoke the caveman-commit skill to ensure every message meets formatting, length, and tone guidelines. The rigid enforcement of the <type>(<scope>): <imperative summary> pattern eliminates style drift between developers.

Rapid Drafting After Staging Changes

When developers finish a set of changes, typing /caveman-commit returns a concise, ready-to-paste message instantly. This eliminates the context-switching overhead of manually composing commit messages while adhering to the 50-character subject line limit.

CI/CD Pipeline Integration

In build pipelines, the skill can process staged changes to generate messages for automated git commit steps. Because it only outputs text without performing Git operations, it can safely run in isolated CI environments before the actual commit command executes.

Enforcing Context for Breaking Changes

For breaking changes or security fixes, SKILL.md lines 22-27 mandate body text explaining the "why" behind the change. This guarantees future debuggers have necessary context when encountering significant modifications in the project history.

Reducing Commit History Noise

By stripping filler words ("added", "now"), AI attribution, and filename restatements as specified in lines 29-34, the skill produces terse commit logs focused purely on functional intent. This reduces cognitive load when reviewing project history.

Practical Implementation Examples

The following examples demonstrate how to invoke the skill based on the implementation in commands/caveman-commit.md and skills/caveman-commit/README.md.

Explicit command invocation:

/caveman-commit

This triggers analysis of the current staged diff and returns output like:

feat(api): add GET /users/:id/profile

Mobile client needs profile data without the full user payload
to reduce LTE bandwidth on cold-launch screens.

Closes #128

Automated Git hook integration:

if git diff --cached --quiet; then
  # No staged changes → skip

else
  /caveman-commit > .git/COMMIT_MSG
  git commit -F .git/COMMIT_MSG
fi

This pattern generates the message, stores it temporarily, and completes the commit without manual intervention.

Summary

• The caveman-commit skill generates Conventional Commit messages without executing Git commands, ensuring zero side effects on repository state.
• Rule enforcement in skills/caveman-commit/SKILL.md mandates strict subject line formatting (≤50 characters), conditional body text, and exclusion of filler content.
• Primary use cases include team standardization, rapid message drafting, CI/CD automation, breaking change documentation, and commit history noise reduction.
• The skill integrates via /caveman-commit commands or natural language triggers defined in commands/caveman-commit.md.

Frequently Asked Questions

Does the caveman-commit skill modify Git history?

No. According to line 65 of skills/caveman-commit/SKILL.md, the skill performs no Git operations itself. It outputs only text, leaving the decision to stage, commit, or amend entirely to the user.

What file contains the formatting rules for commit messages?

The complete rule set resides in skills/caveman-commit/SKILL.md. Lines 14-20 define subject line constraints, lines 22-27 specify body requirements, and lines 29-34 list prohibited content patterns.

Can I use caveman-commit in automated CI/CD pipelines?

Yes. Because the skill only generates text output without side effects, you can safely invoke it in pipelines to create commit messages for automated Git operations. The generated message can be piped to git commit -F or equivalent commands.

How does the skill handle breaking changes?

For breaking changes, the skill mandates body text explaining the reasoning behind the change, as specified in lines 22-27 of SKILL.md. This ensures that significant modifications include necessary context for future maintainers.

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}