Plan Elixir/Phoenix Feature

Plan a feature by spawning Elixir specialist agents, then output structured plan with checkboxes.

What Makes /phx:plan Different from /plan

1. •Spawns Elixir specialist agents for research
2. •Plans with [ecto], [liveview], [oban] task routing
3. •Checks for Iron Law compliance in the plan
4. •Includes mix compile/format/credo/test verification
5. •Understands Phoenix context boundaries

Usage

/phx:plan Add user avatars with S3 upload
/phx:plan .claude/plans/playwright/reviews/playwright-review.md
/phx:plan Implement notifications --depth deep
/phx:plan .claude/plans/auth/plan.md --existing

Arguments

• •$ARGUMENTS = Feature description, review file, or existing plan
• •--depth quick|standard|deep = Planning depth (auto-detected)
• •--existing = Enhance an existing plan with deeper research

Workflow

1. •Gather context — File path (skip to agents), clear description, or vague/fuzzy (needs clarification)
2. •Clarify if vague — Ask questions ONE at a time
3. •Detect depth — Auto-detect quick/standard/deep
4. •Runtime context (Tidewave) — Gather live schemas, routes, and warnings before spawning agents (see planning-orchestrator)
5. •Spawn research agents — Selective, parallel, based on need
6. •Wait for ALL agents — NEVER write plan while agents run
7. •Breadboard (LiveView) — System map for multi-page features
8. •Completeness check — MANDATORY when planning from review
9. •Split decision — One plan or multiple, concrete options
10. •Generate plan — Checkboxes, phased tasks, code patterns
11. •Self-check (deep only) — Three questions in Risks section
12. •Present and ask — STOP, show summary, let user decide

When planning from review: Every finding must appear in the plan — either as a task OR explicitly deferred by the user.

See references/planning-workflow.md for detailed step-by-step.

--existing Mode (Deepening)

Enhances an existing plan instead of creating a new one:

1. •Load plan, search .claude/solutions/ for known risks
2. •Spawn focused research agents for thin sections
3. •Add implementation detail, resolve spikes, add verification
4. •Present diff summary — NEVER delete existing tasks

Iron Laws

1. •NEVER auto-start /phx:work — Always present plan and ask
2. •Research before assuming — Web-search unfamiliar tech
3. •Spawn agents selectively — Only relevant, not all
4. •NEVER write plan while agents still running
5. •NEVER skip input findings — Every finding MUST have a task
6. •Do NOT spawn hex-library-researcher for existing deps

Integration with Workflow

/phx:plan {feature}  <-- YOU ARE HERE
       |
   /phx:plan --existing (optional enhancement)
       |
   ASK USER -> /phx:work .claude/plans/{feature}/plan.md
       |
/phx:review → /phx:compound

Notes

• •Plans saved to .claude/plans/{slug}/plan.md
• •Research reports in .claude/plans/{slug}/research/ can be deleted after

CRITICAL: After Writing the Plan

STOP. Do NOT proceed to implementation.

After writing .claude/plans/{slug}/plan.md:

1. •Summarize: task count, phases, key decisions
2. •Use AskUserQuestion with options:
   • •"Start in fresh session" (recommended for 5+ tasks)
   • •"Start here"
   • •"Review the plan"
   • •"Adjust the plan"
3. •Wait for user response. Never auto-start work.

This is Iron Law #1. Violating it wastes user context.

References (DO NOT read — for human reference only)

• •references/planning-workflow.md — Detailed step-by-step
• •references/plan-template.md
• •references/complexity-detail.md
• •references/example-plan.md
• •references/agent-selection.md
• •references/breadboarding.md