Rails Bug Triage

Use this skill when a bug report exists but the right reproduction path and fix sequence are not yet clear.

Core principle: Do not guess at fixes. Reproduce the bug, choose the right failing spec, then plan the smallest safe repair.

Process

1. Capture the report: Restate the expected behavior, actual behavior, and reproduction steps.
2. Bound the scope: Identify whether the issue appears in request handling, domain logic, jobs, engine integration, or an external dependency.
3. Gather current evidence: Logs, error messages, edge-case inputs, recent changes, or missing guards.
4. Choose the first failing spec: Pick the boundary where the bug is visible to users or operators.
5. Define the smallest fix path: Name the likely files and the narrowest behavior change that should make the spec pass.
6. Hand off: Continue through rails-tdd-slices -> rspec-best-practices -> implementation skill.

Triage Output

Return findings in this shape:

1. Observed behavior
2. Expected behavior
3. Likely boundary
4. First failing spec to add
5. Smallest safe fix path
6. Follow-up skills

Example (wrong status code bug):

1. Observed:  POST /orders returns 500 when product is out of stock
2. Expected:  Returns 422 with { error: "Out of stock" }
3. Boundary:  Request layer — visible in HTTP contract
4. First spec: spec/requests/orders/create_spec.rb
5. Fix path:  Orders::CreateOrder should return { success: false, error: "Out of stock" }
              when inventory check fails; controller renders 422
6. Next:      rails-tdd-slices → write request spec → rspec-best-practices → fix

Skeleton failing spec:

# spec/requests/orders/create_spec.rb
RSpec.describe "POST /orders", type: :request do
  context "when product is out of stock" do
    let(:product) { create(:product, stock: 0) }

    it "returns 422 with an error message" do
      post orders_path, params: { order: { product_id: product.id, quantity: 1 } }, as: :json
      expect(response).to have_http_status(:unprocessable_entity)
      expect(response.parsed_body["error"]).to eq("Out of stock")
    end
  end
end

Run it before implementing the fix: bundle exec rspec spec/requests/orders/create_spec.rb

Boundary Guide

See BOUNDARY_GUIDE.md for the full bug-shape → spec-type mapping and layer diagnosis tips.

Quick reference:

Pitfalls

Integration