Rules

Rules are the core configuration unit in AgentsMesh. Each rule is a Markdown file with optional YAML frontmatter stored in .agentsmesh/rules/.

The root rule

_root.md is the only required file. It is always applied regardless of target, scope, or glob.

---
root: true
---

# Project Guidelines

- Write tests before implementation.
- Max 200 lines per file.
- Use TypeScript strict mode.
- Prefer pure functions over classes.

Note

The filename _root.md is reserved. AgentsMesh always treats it as always-on and required.

Additional rules

Additional rules live alongside _root.md and can be scoped by target, glob pattern, or left unscoped (applied to all targets).

Unscoped rule (all targets)

---
description: Security conventions
---

Never log sensitive data. Validate all external inputs.
Use parameterized queries. Avoid `eval()`.

Target-scoped rule

---
description: Frontend conventions
targets: [cursor, claude-code]
globs: [src/components/**/*.tsx]
---

Use functional components with hooks. No class components.
Prefer Tailwind utility classes over custom CSS.

Codex CLI rule with instruction variant

---
description: Codex execution rule
codexEmit: execution
codexInstructionVariant: override
---

Always run `pnpm typecheck` before committing.

Frontmatter reference

Field	Type	Description
root	boolean	Always-applied rule. Required for _root.md.
description	string	Human-readable rule name shown in tool menus.
targets	string[]	Limit rule to specific tools. Empty = all targets. See the supported tools matrix for valid IDs.
globs	string[]	File patterns this rule applies to (tool-dependent). Uses gitignore-style glob syntax.
trigger	string	Windsurf activation mode: always_on, model_decision, glob, manual.
codexEmit	string	Codex CLI instruction type: advisory or execution.
codexInstructionVariant	string	Codex nested instruction format: default or override.

Tool-specific behavior

Rules are mapped to each tool’s native format during generation. See the Rules row in the supported tools matrix for per-target support levels and the generate output locations for target directory mappings.

Some targets fold additional rules into a root or aggregate instruction file. In those cases AgentsMesh wraps each embedded rule in a managed embedding block so repeated generation does not append duplicates and import can restore the rule to .agentsmesh/rules/*.md.

File naming

Rule filenames become the rule identifier in tool menus. Use kebab-case descriptive names:

.agentsmesh/rules/
  _root.md
  security.md
  frontend-react.md
  backend-api.md
  testing.md

No name collisions are allowed. AgentsMesh lints for duplicate rule names during agentsmesh lint.