crystal-lang/crystal

At a glance

Rank

#320 of 401

Checks passed

7 of 17

Full list below

Best set up for

Devin

Score 63.1

Needs most work for

Cursor

Biggest fix: Cursor rules (.cursor/rules) (+11.5 pts)

What to fix first

Showing fixes for Claude Code

1. 1
   AGENTS.md / CLAUDE.md

   Add an AGENTS.md covering project goals, layout, setup commands, and conventions. Aim for 800+ chars of real guidance (not boilerplate).
   +13.2 pts
2. 2
   Linter / formatter config

   Configure a linter/formatter (ESLint+Prettier, Biome, Ruff, rustfmt+clippy, golangci-lint) and commit the config.
   +7.9 pts
3. 3
   Type configuration

   Add a type config (tsconfig.json for JS/TS, mypy.ini or pyrightconfig.json for Python). Rust/Go/JVM/Scala/Swift/C#/OCaml/Haskell/Zig are typed by default.
   +7.9 pts

Score for each AI agent

Each agent weighs the checks by its own docs. Under each score are its top three. How each agent is scored →

Does crystal-lang/crystal have agent instructions?

An AGENTS.md (or CLAUDE.md) at the root tells AI coding agents how to build, test and work in the repo. A few agents also read a file of their own.

AGENTS.md / CLAUDE.md

✗None at the root (no AGENTS.md, CLAUDE.md, AGENT.md, .claude/CLAUDE.md or .claude/AGENTS.md)

Agent-specific files

None: no GEMINI.md, .cursor/rules, .openhands/setup.sh, .aider.conf.yml or .agents/skills

Repos that have one

221 of 401 repos on the leaderboard · See examples →

# AGENTS.md

Guidance for AI coding agents working in crystal-lang/crystal. The Crystal Programming Language. Written mainly in Crystal.

## Where things are

- Dependencies are declared in `shard.yml`.
- Tests live in `spec`.
- CI is defined in `.github/workflows`; read it for the exact install, lint and test steps.
- Common tasks are targets in `Makefile`.
- Follow the conventions in `CONTRIBUTING.md`.

## Commands

<!-- Fill in the exact commands CI runs. -->
- Install: TODO
- Test: TODO
- Lint: TODO

How crystal-lang/crystal compares

vs leaderboard average

10.0 pts below

Average 66.8

One fix for the most agents: Linter / formatter config would raise the score for all 9 agents, by up to 14.1 points.

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