Give your agent Chelis

Give your coding agent the language rules, then have it check each program with the compiler.

Where to put it

As a skill: Save SKILL.md in its own folder in your agent's skills directory.
In your instructions: Reference it from your project's AGENTS.md or CLAUDE.md.
For one session: Paste the prompt at the start of the session.

The skill

https://chelis.ch/SKILL.md

Or paste this into your agent

Read https://chelis.ch/SKILL.md and use it when writing Chelis.

For writing programs and installing dependencies. No compiler source checkout needed.

Save the program as app.ch. Format it, then check it. Read the JSON report and fix its errors before evaluating it.

$ chelis fmt --inplace app.ch
$ chelis check app.ch
$ chelis eval --file app.ch --json

In a Reef project, keep its compiler pin and run chelis reef setup to install dependencies. For a first standalone program, use the worked lessons.

Compiler workflow
chelis check app.ch
Read JSON diagnostics, evaluate code, and check MCP connection requirements.
Set up compiler access
llms.txt
/llms.txt
The pages an agent should read first.
Open llms.txt
Worked lessons
addition.ch
Small programs, their results, and changes to try.
Start with a program