format-code - SKILL.md Agent Skill

name: format-code description: Formats the codebase using nightly rustfmt. Use when asked to "format the code", "run rustfmt", "cargo fmt", or when formatting is needed after code changes. context: root user-invocable: true

Format Code

Description

Formats all Rust code in the codebase using nightly rustfmt to ensure consistent code style. This skill always uses nightly rustfmt to access the latest formatting features and configurations.

When to Use

When asked to "format the code" or "format my code"
When asked to "run rustfmt" or "cargo fmt"
When asked to "fix formatting" or "clean up formatting"
After completing code changes that need formatting
Before committing changes to ensure consistent style
When formatting issues are flagged by CI or pre-commit hooks

How It Works

Step 1: Run Nightly Rustfmt

Execute the format command using nightly toolchain:

cargo +nightly fmt

This formats all Rust files in the workspace according to the project's rustfmt.toml configuration (if present).

Step 2: Report Results

After formatting completes:

If changes were made, inform the user that files were formatted
If no changes were needed, confirm the code was already properly formatted
Report any errors that occurred during formatting

Example Usage

User Request: "Format the code"

Expected Behavior:

Run formatter:
```
cargo +nightly fmt
```
Check for changes (optional):
```
git status
```

Report:

Code formatted successfully using nightly rustfmt.

User Request: "Run rustfmt before I commit"

Expected Behavior:

Run formatter:
```
cargo +nightly fmt
```
Report:
```
Formatting complete. Ready to commit.
```

Best Practices

Do:

Always use cargo +nightly fmt to ensure nightly toolchain
Run formatting before committing changes
Report whether any files were modified by the formatter

Don't:

Use cargo fmt without the +nightly flag
Skip formatting when making code changes
Ignore formatting errors

Quality Checklist

Before considering the task complete, verify:

Ran cargo +nightly fmt successfully
No formatting errors were reported
User is informed of the result

Troubleshooting

Nightly toolchain not installed:

Run rustup install nightly to install
Then retry the format command

Formatting fails with parse errors:

Check for syntax errors in the Rust code
Fix compilation errors first, then format

rustfmt.toml issues:

Verify the configuration file is valid
Check that nightly-only options are supported

Related Skills

create-git-commit - Create commits after formatting
Code quality and linting workflows