Examples & Walkthroughs
Official Phoenix Guides (Reference)
For standard implementation patterns, always check official guides first:
| Topic | Guide |
|---|---|
| Contexts | hexdocs.pm/phoenix/contexts |
| Ecto Basics | hexdocs.pm/phoenix/ecto |
| LiveView | hexdocs.pm/phoenix_live_view |
| Authentication | mix phx.gen.auth |
| Channels | hexdocs.pm/phoenix/channels |
| Testing | hexdocs.pm/phoenix/testing |
| Deployment | hexdocs.pm/phoenix/deployment |
Plugin-Specific Patterns
Patterns NOT in official guides (unique to this plugin):
Tidewave Integration Workflow
bash
# 1. Check if Tidewave is running /mcp # 2. If connected, debug with runtime tools # Get exact docs for YOUR dependency versions mcp__tidewave__get_docs "Ecto.Query" # Execute code in running app mcp__tidewave__project_eval "MyApp.Accounts.list_users() |> length()" # Query database directly mcp__tidewave__execute_sql_query "SELECT count(*) FROM users"
Multi-Agent Review Workflow
bash
# 1. Plan feature with specialist agents /phx:plan Add user avatars with S3 upload # 2. After implementation, review with multiple perspectives /phx:review lib/my_app/accounts.ex # Elixir idioms # Security analyzer runs automatically on auth code # 3. Before deployment # Deployment validator checks production readiness
Iron Laws Enforcement
This plugin enforces non-negotiable rules across all agents:
Elixir Idioms:
- •NO process without runtime reason
- •Messages are copied (keep small)
- •Changesets for external data
LiveView:
- •NEVER query DB in mount
- •ALWAYS use streams for lists
- •RE-AUTHORIZE in every handle_event
Oban:
- •Jobs MUST be idempotent
- •ALWAYS handle {:error, _} returns
- •Use unique keys for deduplication
Security:
- •Validate at boundaries
- •Never interpolate user input in queries
- •Authorize everywhere (not just mount)
Example Workflows
Bug Investigation
bash
# 1. Start with obvious checks /phx:investigate Login failing after password reset # 2. Agent checks Ralph Wiggum list: # - File saved? Compiled? Migrated? # - Atom vs string keys? # - Data preloaded? # 3. If complex, escalate to Ralph Wiggum Loop (if installed) /ralph-loop:ralph-loop "Fix login tests. Output <promise>DONE</promise> when green."
Feature Planning
bash
# 1. Research phase /phx:research Oban unique jobs best practices # 2. Plan with context analysis /phx:plan Add daily digest email job # 3. Agents coordinate: # - hex-library-researcher evaluates deps # - oban-specialist designs worker # - ecto-schema-designer plans data model
Security Audit
bash
# 1. Run security analyzer on auth code /phx:review lib/my_app_web/controllers/session_controller.ex # 2. Check for common vulnerabilities: # - SQL injection (parameterized queries?) # - XSS (proper escaping?) # - CSRF (tokens present?) # - Authorization (re-checked in events?)
When to Use Official Docs vs Plugin
| Situation | Use |
|---|---|
| "How do I create a context?" | Official Phoenix guides |
| "Is my context design idiomatic?" | Plugin's /phx:review |
| "How do I add LiveView?" | Official LiveView guides |
| "Does my LiveView have memory issues?" | Plugin's Iron Laws |
| "How do I deploy to Fly.io?" | Official deployment guide |
| "Is my release config production-ready?" | Plugin's deployment-validator |