cross-layer-check

name	cross-layer-check
description	Verify that a new field, enum value, or status code exists consistently across all layers. Use after adding new fields to prevent cross-layer inconsistency (DB → service → API → tests).

Cross-Layer Check Skill

Verify a symbol is consistently propagated across all layers.

When to use

• Added a new field to a model/schema
• Added a new enum value
• Added a new API endpoint or status code
• Renamed a field anywhere in the stack
• After any change that touches a shared data contract

Protocol

1. Identify the symbol

What is the exact name of the new/changed field, enum value, or endpoint?

2. Grep across all layers

# Search for the symbol everywhere
grep -rn --color=never '<symbol_name>' . \
  --include='*.ts' \
  --include='*.js' \
  --include='*.py' \
  --include='*.go' \
  --include='*.java' \
  --include='*.sql' \
  | grep -v 'node_modules\|.git\|dist\|build' \
  | head -50

3. Verify presence in each layer

Check the following layers (adapt to your stack):

Layer	What to check
DB schema	Migration file, model definition
Repository/DAO	Query selects/inserts include the field
Service	Business logic handles the new field
Mapper/Serializer	Field mapped in both directions
DTO/Type	Type definition includes the field
Validator	Field validated if required
API response	Field included in response schema
API tests	Tests assert the field in responses
Unit tests	Tests cover the new enum value/case
Docs/OpenAPI	Spec updated (if applicable)

4. Identify gaps

For each layer where the symbol is missing:

• Is the absence intentional (the layer doesn't need it)?
• Or is it a bug (it was forgotten)?

5. Fix the gaps

For each genuine gap, apply the minimal fix to add the symbol.

6. Re-run grep to confirm coverage

grep -rn --color=never '<symbol_name>' . | grep -v 'node_modules\|.git' | head -50

7. Run tests

# (use the test command from brain/build.md)

Output

Cross-Layer Check: <symbol_name>
✅ DB schema
✅ Repository
❌ Service — MISSING: field not handled in processOrder()
✅ DTO
❌ Tests — MISSING: no test asserts <symbol_name> in response