> ## Documentation Index
> Fetch the complete documentation index at: https://docs.kodus.io/llms.txt
> Use this file to discover all available pages before exploring further.

# How to create custom code review rules

> Define rules tailored to your team's architecture, patterns, and coding preferences that are enforced automatically on every PR.

Every team has conventions that generic linters don't cover — architecture boundaries, naming patterns, testing requirements, or business-specific constraints. Custom code review rules let you encode these into automated checks.

## Creating a rule in Kodus

1. Go to **Code Review Settings** → **Kody Rules**
2. Click **Add Rule**
3. Configure:
   * **Name** — what the rule checks (e.g., "Service files must have tests")
   * **Scope** — File-level (analyzes individual files) or PR-level (analyzes the entire PR)
   * **Path** — glob pattern to target specific files (e.g., `src/services/**/*.ts`)
   * **Severity** — Critical, High, Medium, or Low
   * **Instructions** — detailed description of what to check

## What makes rules powerful

Rules can access rich context:

* **Variables** like `fileDiff`, `pr_title`, `pr_description`, `pr_files_diff`
* **File references** with `@file:path/to/file.ts` to compare against patterns
* **MCP functions** to fetch data from connected tools (Jira, repository structure, etc.)

### Example: Architecture boundary rule

```
Name: Domain layer must not depend on infrastructure
Scope: Pull Request
Instructions: Check pr_files_diff for any import in src/domain/
that references src/infrastructure/. Reference
@file:docs/architecture.md for allowed dependencies.
```

### Example: Test coverage rule

```
Name: Every service must have a test file
Scope: Pull Request
Instructions: For each file modified in src/services/,
verify a corresponding test file exists in test/services/.
Use MCP to check the repository file tree.
```

## More ways to add rules

* **Import from Rules Library** — browse proven rules by language and category
* **Sync from IDE tools** — auto-import rules from Cursor, Copilot, Claude
* **Repository rules** — define rules in markdown files in your repo
* **Auto-generation** — Kody suggests rules based on your review history

For the full reference, see [Kody Rules](/how_to_use/en/code_review/configs/kody_rules).