MoonBit System Prompt

Agents.mbt.md contains the MoonBit System Prompt, a descriptive system prompt designed to enhance the performance of code agents over MoonBit projects.

How to use

The simplest way is to reference the file and ask the AI to read it in the prompt.

Here we provide some extra instructions on how to use the MoonBit System Prompt in different code agents.

AGENTS.md

Many AI code agents now have adopted the AGENTS.md convention for providing guidance for agents. For such agents, you may:

• Copy Agents.mbt.md into your project directory as AGENTS.md
• Append the content of Agents.mbt.md to your existing AGENTS.md file.

Claude Code

Claude Code supports CLAUDE.md file. Since CLAUDE.md supports @path/to/import syntax, we suggest copying Agents.mbt.md into your project directory and mention it in CLAUDE.md. For example, suppose you copied Agents.mbt.md to your project directory as moonbit.mbt.md, then you can add the following line to your CLAUDE.md file:

# MoonBit Language Reference
- @moonbit.mbt.md

See Memory Management on detailed configuration.

Codex CLI

Codex CLI supports AGENTS.md. Quoted from openai/codex/docs/getting-started.md:

You can give Codex extra instructions and guidance using AGENTS.md files. Codex looks for AGENTS.md files in the following places, and merges them top-down:

1. ~/.codex/AGENTS.md - personal global guidance
2. AGENTS.md at repo root - shared project notes
3. AGENTS.md in the current working directory - sub-folder/feature specifics

For more information on how to use AGENTS.md, see the official AGENTS.md documentation.

Cursor & Cursor CLI

Cursor supports AGENTS.md files. See the AGENTS.md section above for details.

Also, one can use rules to include the content of Agents.mbt.md file. For project rule, you can copy Agents.mbt.md to .cursor/rules/moonbit.mdc, and configure ways to include the context in the front-matter of .cursor/rules/moonbit.mdc. For example:

---
description: "MoonBit System Prompt"
globs:
alwaysApply: true
---
...

See https://docs.cursor.com/en/context/rules for more details.

Cursor CLI supports the same rules system as the IDE

Gemini CLI

Gemini-CLI reads from GEMINI.md files for user-level/repository-specific instructions/contexts. Since it supports @ memory import, we suggest copying Agents.mbt.md into your project directory and mention it in GEMINI.md. For example, suppose you copied Agents.mbt.md to your project directory as moonbit.mbt.md, then you can add the following line to your GEMINI.md file:

# MoonBit Language Reference
- @moonbit.mbt.md

See Memory Import Processor for more information.

Also, Gemini-CLI can be configured to use AGENTS.md files, as per https://agents.md:

How do I configure Gemini CLI?

Configure Gemini CLI to use AGENTS.md in .gemini/settings.json:

{ "contextFileName": "AGENTS.md" }

GitHub Copilot for VS Code

VS Code Copilot experimentally supports AGENTS.md.

When working with multi-language projects, you may want to limit the scope of the system prompt to specifically MoonBit-related files. You can do this by creating a .github/instructions/moonbit.instructions.md file with the following content:

---
applyTo: "**/*.mbt,**/*.mbti,**/moon.mod.json,**/moon.pkg.json,**/*.mbt.md"
---
[Content of Agents.mbt.md]