Project Rules Writer

Create rules that solve a specific problem in a specific project — never generic ones. Analyse the project first, design, confirm with AskUserQuestion, then generate.

Core discipline: understand the problem → analyse the project → design the rule → confirm → generate. No file lands without user confirmation.

Shared writing-discipline rules across this and the other writer skills (project-skill-writer / project-agent-writer / project-skill-installer): see [../project-skill-writer/references/writer-discipline.md](../project-skill-writer/references/writer-discipline.md).

When to use

• "create a rule", "for X create a rule", "set the code style"
• "make the AI always …", "enforce naming convention", "configure AI behaviour"
• User references .agents/rules/..., .trae/rules/..., or #RuleName syntax
• Constrain AI behaviour for a specific project or file pattern

When NOT to use

Prerequisites

• Node.js ≥ 18
• A project where an AI assistant reads project rules (Trae, Cursor, Windsurf, Claude Code, etc.). This writer emits to <project>/.agents/rules/; symlink or sync to .trae/rules/ / .cursor/rules/ if your IDE needs that exact path.

Workflow (5 steps)

L1 Understand the problem  →  L2 Analyse the project  →  L3 Design the rule  →  L4 Confirm  →  L5 Generate + validate

L1 — Understand the problem

Don't ask "what rule do you want?" Infer from the prompt:

Extract: problem, scope (which files/contexts), expected behaviour, exceptions.

L2 — Analyse the project

Run two agents in parallel via the Task tool:

• [project-scanner](agents/project-scanner.md) — structure, existing rules, patterns
• [convention-detector](agents/convention-detector.md) — naming / style / architecture conventions

Detect: language(s), framework, existing rule files (.agents/rules/.md first, then .trae/rules/.md if present), lint/format configs (ESLint, Prettier, EditorConfig, Ruff), naming patterns, layering.

L3 — Design the rule

Apply-mode picker:

Design principles: one problem per rule • follow project conventions • narrowest scope that covers the problem • no conflict with existing rules.

Frontmatter format gotchas (the gate enforces these in L5):

L4 — Confirm (mandatory)

Use AskUserQuestion to present the design before any file is written. Include the rule name, apply mode, and output path. Offer "create / adjust / skip" — and if multiple modes are valid, offer the mode choice as a separate question. Never write a file without user confirmation. If the user says "adjust", loop back to L3.

L5 — Generate + validate

node scripts/cli.cjs init \
  --skill-dir <this-skill-dir> \
  --name <rule-name> \
  --description "<when-this-rule-applies>" \
  --output-dir <project>/.agents/rules/

Fallback: if init doesn't fit, write the .md file directly using [assets/rule.md.template](assets/rule.md.template).

Then run [quality-validator](agents/quality-validator.md). Pre-delivery checklist:

• globs: comma-separated, no quotes, no array
• No absolute paths in rule content
• description present and explains when the rule applies
• alwaysApply and globs not both active
• No conflict with existing rules (from L2 analysis)
• Rule content is actionable (specific constraints, not vague advice)
• Content in English

Delivery report

Rule created:
  Name:    {rule-name}
  Mode:    {always|file-specific|smart|manual}
  Path:    {project-relative path}

Frontmatter:
  description: {value}
  globs:       {value if applicable}
  alwaysApply: {value}

Usage: {one-line note on how it fires}

Error handling

Boundaries

This skill only: analyses project context, designs a rule, confirms with the user, generates a frontmatter+markdown .md at <project>/.agents/rules/ (project-relative, IDE-neutral), validates the result.

This skill does not: create skills (→ project-skill-writer), create agents (→ project-agent-writer), install skills (→ project-skill-installer), edit any IDE's own settings, or install rules globally.

Agents and references

• Agents: [project-scanner](agents/project-scanner.md), [convention-detector](agents/convention-detector.md), [quality-validator](agents/quality-validator.md)
• [references/rule-types.md](references/rule-types.md) — pick the right rule type from a problem
• [examples/application-modes.md](examples/application-modes.md) — all four apply modes with frontmatter examples
• [assets/rule.md.template](assets/rule.md.template) — scaffold
• [assets/trae-rules-docs.md](assets/trae-rules-docs.md) — vendored frontmatter format reference (originally from Trae's rules doc; format is shared across Trae / Cursor / Windsurf)