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Rule Chaining

The depends_on field lets you skip rules when a prerequisite rule has not passed.

Basic usage​

rules:
  - name: has-migration-file
    type: regex
    pattern: 'migrations/'
    match: true
    on_fail: warn

  - name: migration-has-rollback
    type: llm
    prompt: |
      Does this database migration include a rollback/down migration?
      Answer YES or NO.
    depends_on: has-migration-file
    on_fail: warn

In this example, migration-has-rollback only runs if has-migration-file passed. If the diff contains no migration files, the second rule is skipped entirely.

Why use depends_on?​

Without chaining, rules run unconditionally. This can cause false positives when a rule's check is only meaningful in certain contexts.

Common patterns:

  • Skip semantic checks when the relevant file type isn't present
  • Skip style checks when the change is a deletion-only diff
  • Skip test coverage checks when only documentation changed

Skip behavior​

When a rule is skipped due to depends_on, it appears in output as:

SKIP  migration-has-rollback     Skipped: depends_on has-migration-file (not passed)

Skipped rules do not affect the exit code.

Chaining multiple rules​

A rule can only reference one depends_on target. For multi-condition gating, chain rules sequentially:

rules:
  - name: is-python-change
    type: regex
    pattern: '\.py'
    match: true

  - name: has-type-hints
    type: ast
    check: missing_docstring
    depends_on: is-python-change

  - name: type-hints-reviewed
    type: llm
    prompt: "Are the type hints in this diff consistent and correct? YES or NO."
    depends_on: has-type-hints

depends_on reference resolution​

The depends_on value must match the name field of another rule exactly. Rules are resolved in declaration order — you can only depend on rules declared earlier in the file.

Next steps​

MCP Server overview to use Comply inside Claude Desktop and Cursor.