ODW #6: The Pros and Cons of MCP and Agent Skills from a Git Automation Perspective (opens in new tab)
The post presents agent skills as a simpler, more practical alternative to building MCP servers for many AI-agent workflows. It demonstrates how to use Anthropic’s skill-creator to build a Git release automation skill that analyzes commits, updates a changelog, bumps versions, commits, tags, and pushes releases. The author emphasizes that precise requirements and explicit constraints are essential for preventing unintended agent behavior.
Why Agent Skills Are Practical
- Agent skills can simplify both implementation and architecture compared with custom MCP servers.
- Although online examples explain the concept, the post focuses on a practical, work-oriented use case.
- The tutorial assumes familiarity with the basic concept of skills and concentrates on building and applying one.
Git Smart Release Automation
The example skill automates releases for a Git project in the current working directory.
- Reads the Git history after the most recent tag.
- Summarizes changes and adds them to the top of
CHANGELOG.md. - Creates
CHANGELOG.mdif it does not exist. - Updates the version in
pyproject.toml. - Commits the changelog and version changes.
- Creates a corresponding Git tag.
- Operates based on the terminal’s current
pwd.
Using skill-creator
- Anthropic’s official
skill-creatorskill is used to generate the new automation skill. - The user provides a detailed requirements specification rather than implementing everything manually.
- Explicit workflow steps and constraints help keep the agent focused on the correct directory and avoid unnecessary complexity.
- The development process is demonstrated with Claude Code.
Clarifying Requirements
Before generating the skill, the agent asks questions to resolve ambiguous behavior.
- Support patch, minor, and major version bumps.
- Use
v0.1.0for the first release when no prior tag exists. - Follow a structured changelog format.
- Push both commits and tags to the remote repository.
- Abort with an explanation if the working directory contains uncommitted changes.
Generated Skill Structure
The completed skill contains:
SKILL.md— instructions and metadata for the agent.scripts/smart_release.py— a local Python script that performs Git operations and file modifications.evals/evals.json— evaluation cases for testing the skill.
The skill also includes:
- Keep a Changelog-style updates.
- Dirty working-directory checks.
- Automatic remote pushing.
- Commit categorization such as
feat,fix, anddocs.
SKILL.md and the Python Script
- The frontmatter in
SKILL.mdacts as a concise discovery description that helps the agent decide when to load the skill. - The Markdown body provides the detailed execution workflow.
smart_release.pyhandles operations requiring deterministic file and Git manipulation, reducing the need for the language model to process raw data directly.- The post then begins testing the skill with a simple Python calculator project.
A practical approach is to define release behavior, edge cases, and safety constraints before asking an agent to generate the skill, while delegating file and Git operations to a local script.