Rails Agent Skills
This skill coordinates disciplined Rails development by sequencing atomic skills for each task. It defines what to run, in what order, and how to validate each step.
Core principle: Atomic, task-specific instructions that turn AI coding assistants into reliable Rails collaborators through TDD and idiomatic patterns.
Activating Atomic Skills
To activate an atomic skill, read its corresponding Markdown file from the skills bundle and follow its instructions as the operative prompt for that step. If a skill file is unavailable, use the inline fallback guidance in the Skill Catalog below rather than halting entirely — note any gaps in output and proceed with best-effort idiomatic Rails conventions.
HARD-GATES
1. Context First (Pre-flight)
- Do not perform any implementation or review action without first running
load-context. - Synchronize with the host application's schema, routes, and established patterns before producing any output.
2. Tests Gate Implementation
- Implementation code cannot be written until a test exists for the target behaviour.
- The test must be executed via
bundle exec rspec <spec_file>before implementation begins. - The test must fail for the correct reason (feature missing, not a syntax error) before proceeding.
Core Process
- Context Initialization (CRITICAL): Activate
load-context. Confirm schema, routes, and patterns are loaded before any other step. - Discovery: Identify which atomic skills from the catalog match the current task.
- Execution Loop:
- Plan: Activate
plan-tests. Output: a list of pending test cases with descriptions. - Act: Activate
write-tests. Runbundle exec rspec <spec_file>— confirm output shows red (failure for the right reason). Then activateimplement. Runbundle exec rspec <spec_file>— confirm green. Then activateapply-code-conventions. - Polish: Activate
write-yard-docsandcode-review.
- Plan: Activate
- Validation: After each atomic skill completes, verify its declared
Output Stylechecklist before proceeding to the next step. If a step produces unexpected failures, re-runload-contextbefore retrying.
Worked Example: Adding a Service Object with Tests
Step 1 — load-context
Input: project root directory
Action: Read schema.rb, routes.rb, and existing service objects
Output: Confirmed patterns (e.g., services inherit ApplicationService, use call)
Step 2 — plan-tests
Input: "Create an OrderFulfillmentService"
Output: [
"returns success when inventory is available",
"returns failure when inventory is insufficient",
"enqueues FulfillmentJob on success"
]
Step 3 — write-tests
Input: test plan above
Output: spec/services/order_fulfillment_service_spec.rb (written, not passing)
Validate: bundle exec rspec spec/services/order_fulfillment_service_spec.rb
→ Expect: 3 examples, 3 failures (NameError or similar — feature missing)
Step 4 — implement
Input: failing spec
Output: app/services/order_fulfillment_service.rb
Validate: bundle exec rspec spec/services/order_fulfillment_service_spec.rb
→ Expect: 3 examples, 0 failures
Step 5 — apply-code-conventions + write-yard-docs + code-review
Output: Linted file with YARD docs and review comments resolved
Skill Catalog
| Category | Skill | Fallback Guidance (if file unavailable) |
|---|---|---|
| Context | load-context | Read schema.rb, routes.rb, and a sample service/model; note conventions manually |
| Testing | plan-tests | List expected behaviours as RSpec it descriptions before writing code |
| Testing | write-tests | Write RSpec examples using described_class, let, expect, have_received idioms |
| Testing | test-service, triage-bug | Follow standard RSpec unit-test patterns; isolate dependencies with doubles |
| DDD | define-domain-language, model-domain, review-domain-boundaries | Apply standard DDD vocabulary; group by bounded context |
| Quality | code-review, security-check, apply-code-conventions, refactor-code | Apply Rails best practices, Brakeman findings, and RuboCop rules inline |
| API/Infra | implement-graphql, integrate-api-client, implement-background-job, review-migration | Follow graphql-ruby conventions, ActiveJob patterns, and strong-migration rules |
| Engines | create-engine, test-engine, release-engine, document-engine | Use rails plugin new --mountable; isolate specs under spec/ inside the engine root |
| Patterns | create-service-object, write-yard-docs | Inherit ApplicationService, expose .call, document with @param/@return YARD tags |
| Setup | setup-environment | Verify Ruby version, bundle install, and bin/rails db:setup |
The complete list of all 28 local atomic skills is defined in tile.json at the project root. This repository also depends on igmarin/ruby-core-skills for 15 additional core skills (Process, Code Quality, Orchestration, DDD, and Ruby patterns).
Integration
tile.json(project root): Canonical registry of all 28 local atomic skills — names, file paths, and metadata. This is the source of truth for skill discovery.docs/reference/skill-catalog.md: Human-readable reference with usage notes for each skill; useful for manual lookup whentile.jsonis unavailable.skill-router: Orchestration layer that maps incoming tasks to the correct atomic skill sequence; invoked automatically when this entry-point skill is activated.
Core Dependencies
This repository depends on igmarin/ruby-core-skills for foundational DDD and Ruby pattern skills. The following 15 core skills are auto-detected and available when this plugin is installed alongside ruby-core-skills:
DDD Skills (3):
define-domain-language— Domain terms glossaryreview-domain-boundaries— Review bounded contexts and language leakagemodel-domain— Map DDD to Rails (models, services, value objects)
Ruby Pattern Skills (4):
create-service-object—.callpattern, response contract, YARDintegrate-api-client— Layered architecture for external APIsimplement-calculator-pattern— Variant-based calculatorswrite-yard-docs— Inline documentation with YARD
Process Skills (5):
tdd-process— TDD discipline and workflowrefactor-process— Refactor preserving behaviorreview-process— Systematic code reviewsecurity-review-process— Security audit workflowtest-planning-process— Test planning and selection
Code Quality Skills (2):
triage-bug— Bug diagnosis and reproductionrespond-to-review— Respond to review feedback
Orchestration Skills (1):
skill-router— Routes to correct specialized skill