Opencode Rules Writing

OpenCode Rules Writing

Rules

1. NEVER place global rules in project AGENTS.md
2. ALWAYS test rule precedence before deployment
3. NEVER reference external files without fallbacks
4. ALWAYS document external dependencies
5. NEVER duplicate rules across files
6. ALWAYS use trigger words: AGENTS.md, opencode.json, rule precedence, external references

Validation

After writing rules:

• Does AGENTS.md use project-specific language?
• Does opencode.json include remote URL patterns?
• Are external file references properly documented?
• Would skill trigger if user mentions "AGENTS.md" or "rule precedence"?

Patterns

AGENTS.md structure for precedence:

# Project Name

## Structure
- packages/ - workspace packages
- infra/ - infrastructure definitions

## Standards
- Use TypeScript with strict mode
- Shared code in packages/core/

## External References
@docs/guidelines.md - load when referenced

opencode.json for remote rules:

{
  "$schema": "https://opencode.ai/config.json",
  "instructions": ["CONTRIBUTING.md", "https://raw.githubusercontent.com/org/rules/main/style.md"]
}

Anti-patterns

NEVER explain what tools are in rules NEVER create duplicate rules in multiple files NEVER reference external files without fallbacks NEVER ignore rule precedence conflicts