Applies DHH/37signals Rails conventions to Ruby code: fat models, thin controllers, REST purity, Hotwire patterns, database-first approach, avoiding Redis/service objects.
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references/architecture.mdreferences/controllers.mdreferences/frontend.mdreferences/gems.mdreferences/models.mdreferences/testing.mdDesigns and optimizes AI agent action spaces, tool definitions, observation formats, error recovery, and context for higher task completion rates.
Enables AI agents to execute x402 payments with per-task budgets, spending controls, and non-custodial wallets via MCP tools. Use when agents pay for APIs, services, or other agents.
Compares coding agents like Claude Code and Aider on custom YAML-defined codebase tasks using git worktrees, measuring pass rate, cost, time, and consistency.
<essential_principles>
"The best code is the code you don't write. The second best is the code that's obviously correct."
Vanilla Rails is plenty:
What they deliberately avoid:
Development Philosophy:
Specify a number or describe your task. </intake>
<routing>| Response | Reference to Read |
|---|---|
| 1, controller | controllers.md |
| 2, model | models.md |
| 3, view, frontend, turbo, stimulus, css | frontend.md |
| 4, architecture, routing, auth, job, cache | architecture.md |
| 5, test, testing, minitest, fixture | testing.md |
| 6, gem, dependency, library | gems.md |
| 7, review | Read all references, then review code |
| 8, general task | Read relevant references based on context |
After reading relevant references, apply patterns to the user's code. </routing>
<quick_reference>
Verbs: card.close, card.gild, board.publish (not set_style methods)
Predicates: card.closed?, card.golden? (derived from presence of related record)
Concerns: Adjectives describing capability (Closeable, Publishable, Watchable)
Controllers: Nouns matching resources (Cards::ClosuresController)
Scopes:
chronologically, reverse_chronologically, alphabetically, latestpreloaded (standard eager loading name)indexed_by, sorted_by (parameterized)active, unassigned (business terms, not SQL-ish)Instead of custom actions, create new resources:
POST /cards/:id/close → POST /cards/:id/closure
DELETE /cards/:id/close → DELETE /cards/:id/closure
POST /cards/:id/archive → POST /cards/:id/archival
# Symbol arrays with spaces inside brackets
before_action :set_message, only: %i[ show edit update destroy ]
# Private method indentation
private
def set_message
@message = Message.find(params[:id])
end
# Expression-less case for conditionals
case
when params[:before].present?
messages.page_before(params[:before])
else
messages.last_page
end
# Bang methods for fail-fast
@message = Message.create!(params)
# Ternaries for simple conditionals
@room.direct? ? @room.users : @message.mentionees
State as Records:
Card.joins(:closure) # closed cards
Card.where.missing(:closure) # open cards
Current Attributes:
belongs_to :creator, default: -> { Current.user }
Authorization on Models:
class User < ApplicationRecord
def can_administer?(message)
message.creator == self || admin?
end
end
</quick_reference>
<reference_index>
All detailed patterns in references/:
| File | Topics |
|---|---|
| controllers.md | REST mapping, concerns, Turbo responses, API patterns, HTTP caching |
| models.md | Concerns, state records, callbacks, scopes, POROs, authorization, broadcasting |
| frontend.md | Turbo Streams, Stimulus controllers, CSS layers, OKLCH colors, partials |
| architecture.md | Routing, authentication, jobs, Current attributes, caching, database patterns |
| testing.md | Minitest, fixtures, unit/integration/system tests, testing patterns |
| gems.md | What they use vs avoid, decision framework, Gemfile examples |
| </reference_index> |
<success_criteria> Code follows DHH style when:
Important Disclaimers: