How do I install the Code Format skill?

Run npx skillmds@latest add lnsd/code-format in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Code Format safe to use?

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Which AI agents work with Code Format?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Code Format free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Code Format?

LNSD (@lnsd) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Code Format by lnsd — Agent Skill

Name: Code Format
Rating: 4.2 (5 reviews)
Author: LNSD

File contents

Code Formatting Skill

This skill provides code formatting operations for the project codebase, which is a Rust workspace.

When to Use This Skill

Use this skill when you need to:

Format code after editing Rust files
Check if code meets formatting standards
Ensure code formatting compliance before commits

Command Selection Rules

Choose the appropriate command based on the number of crates/files edited:

Scenario	Command	Rationale
1 crate, 1-2 files	`just fmt-file <file>` (per file)	Faster, targeted formatting
1 crate, 3+ files	`just fmt`	More efficient than multiple per-file calls
2+ crates	`just fmt`	Always use workspace-wide formatting

Decision process:

Identify how many crates contain your edited files
If 2 or more crates: use just fmt
If exactly 1 crate with 1-2 files: use just fmt-file for each file
If exactly 1 crate with 3+ files: use just fmt

Available Commands

Format Rust Code

just fmt

Formats all Rust code using cargo +nightly fmt --all. This is the primary formatting command.

Check Rust Formatting

just fmt-check

Checks Rust code formatting without making changes using cargo +nightly fmt --all -- --check.

Format Specific File

just fmt-file <FILE>

Formats a specific Rust file.

Examples:

just fmt-file src/main.rs - formats a Rust file

Important Guidelines

Format Before Checks/Commit

Format code when you finish a coherent chunk of work and before running checks or committing.

This is a critical requirement from the project's development workflow:

Do not skip formatting before checks/commit
Use the Command Selection Rules above to choose the right command
Run formatting before any check or test commands

Example Workflows

Single file edit:

Edit a Rust file: src/common/utils.rs
When ready to validate, run: just fmt-file src/common/utils.rs
Then run checks

Multiple files edit (3+):

Edit multiple Rust files across the codebase
When ready to validate, run: just fmt
Then run checks

Common Mistakes to Avoid

❌ Anti-patterns

Never run cargo fmt directly - Use just fmt-file or just fmt
Never run rustfmt directly - The justfile includes proper flags
Never skip formatting before checks/commit - Even "minor" edits need formatting
Never use just fmt for 1-2 files in a single crate - Use just fmt-file <file> for efficiency
Never use just fmt-file for 2+ crates or 3+ files - Use just fmt for efficiency

✅ Best Practices

Format before running checks/tests or before committing
Use just fmt-file for 1-2 files within a single crate (faster, targeted)
Use just fmt for 2+ crates or 3+ files (more efficient)
Run just fmt-check to verify formatting before commits

Next Steps

After formatting your code:

Check compilation → See .claude/skills/code-check/SKILL.md
Run clippy → See .claude/skills/code-check/SKILL.md
Run targeted tests when warranted → See .claude/skills/code-test/SKILL.md

---name: code-formatdescription: Format Rust code automatically. Use immediately after editing .rs files, when user mentions formatting, code style, or before commits/PRs. Ensures consistent code style following project conventions.---# Code Formatting SkillThis skill provides code formatting operations for the project codebase, which is a Rust workspace.## When to Use This SkillUse this skill when you need to:- Format code after editing Rust files- Check if code meets formatting standards- Ensure code formatting compliance before commits## Command Selection RulesChoose the appropriate command based on the number of crates/files edited:| Scenario | Command | Rationale ||----------|---------|-----------|| 1 crate, 1-2 files | `just fmt-file <file>` (per file) | Faster, targeted formatting || 1 crate, 3+ files | `just fmt` | More efficient than multiple per-file calls || 2+ crates | `just fmt` | Always use workspace-wide formatting |**Decision process:**1. Identify how many crates contain your edited files2. If 2 or more crates: use `just fmt`3. If exactly 1 crate with 1-2 files: use `just fmt-file` for each file4. If exactly 1 crate with 3+ files: use `just fmt`## Available Commands### Format Rust Code```bashjust fmt```Formats all Rust code using `cargo +nightly fmt --all`. This is the primary formatting command.### Check Rust Formatting```bashjust fmt-check```Checks Rust code formatting without making changes using `cargo +nightly fmt --all -- --check`.### Format Specific File```bashjust fmt-file <FILE>```Formats a specific Rust file.Examples:- `just fmt-file src/main.rs` - formats a Rust file## Important Guidelines### Format Before Checks/CommitFormat code when you finish a coherent chunk of work and before running checks or committing.This is a critical requirement from the project's development workflow:- Do not skip formatting before checks/commit- Use the Command Selection Rules above to choose the right command- Run formatting before any check or test commands### Example Workflows**Single file edit:**1. Edit a Rust file: `src/common/utils.rs`2. When ready to validate, run: `just fmt-file src/common/utils.rs`3. Then run checks**Multiple files edit (3+):**1. Edit multiple Rust files across the codebase2. When ready to validate, run: `just fmt`3. Then run checks## Common Mistakes to Avoid### ❌ Anti-patterns- **Never run `cargo fmt` directly** - Use `just fmt-file` or `just fmt`- **Never run `rustfmt` directly** - The justfile includes proper flags- **Never skip formatting before checks/commit** - Even "minor" edits need formatting- **Never use `just fmt` for 1-2 files in a single crate** - Use `just fmt-file <file>` for efficiency- **Never use `just fmt-file` for 2+ crates or 3+ files** - Use `just fmt` for efficiency### ✅ Best Practices- Format before running checks/tests or before committing- Use `just fmt-file` for 1-2 files within a single crate (faster, targeted)- Use `just fmt` for 2+ crates or 3+ files (more efficient)- Run `just fmt-check` to verify formatting before commits## Next StepsAfter formatting your code:1. **Check compilation** → See `.claude/skills/code-check/SKILL.md`2. **Run clippy** → See `.claude/skills/code-check/SKILL.md`3. **Run targeted tests when warranted** → See `.claude/skills/code-test/SKILL.md`

Frequently asked questions

Code Format