Ash Kindle — AI Dev Environment Setup for Ash/Phoenix

You are setting up the AI-assisted development environment for an Ash/Phoenix project. This includes: usage_rules, Tidewave MCP, domain MCP (dev), Ash AI, CLAUDE.md, Claude Code skills, the logging-best-practices skill, and optionally browser testing and dev environment setup (devenv/flake/devbox).

Step 0: Read References

Before doing anything, read the full setup guide and defaults:

Read skills/ash-kindle/references/setup-guide.md
Read skills/ash-kindle/defaults.md

Step 1: Detect Project State

Determine:

• Is this a new or existing project? (check for mix.exs in the directory)
• Is it an umbrella or single app?
• What is the OTP app name? (e.g., my_app)
• What is the web app module? (e.g., MyAppWeb)
• What Ash domains exist? (check ash_domains in config)
• What Phoenix port is configured? (default 4000)
• Are there domain-specific deps beyond Ash? (Oban, Req, LangChain, etc.)
• Which dev environment tool is in use? (check for devenv.nix, flake.nix, or devbox.json)
• Is domain MCP already configured? (check for AshAi.Mcp.Dev in endpoint.ex, "/dev/mcp" in router.ex, @mcp_tools module attribute in router.ex, and a non-tidewave entry in .mcp.json — if all four present, skip; if partially configured, warn the user and offer to complete setup)
• Is browser testing already set up? (check for .claude/skills/browser-testing/SKILL.md)

Use mix.exs, config/config.exs, and the project file structure to answer these.

If no project exists yet

If the directory has no mix.exs, offer to create a new Phoenix project:

1. Install the Phoenix generator: mix archive.install hex phx_new --force
2. Create the project: yes | mix phx.new . --app <app_name>

• The yes | prefix is needed to auto-confirm the existing directory prompt

1. Ask about structure (single app recommended — can migrate to umbrella later)
2. Then proceed with the rest of the setup

Step 2: Ask or Accept Defaults

Present the user with what you'll set up:

I'll configure the following AI dev tooling for your Ash/Phoenix project:

>

1. usage_rules — CLAUDE.md generation + doc search from deps 2. Tidewave — dev MCP server for runtime introspection (eval, logs, schemas) 3. Domain MCP — dev-only MCP server exposing your Ash domain tools (requires Ash domains with resources) 4. Ash AI — usage rules and MCP tooling for Ash resources 5. CLAUDE.md — project instructions (Ash First, MCP Usage, Feedback Loop, Logging) 6. Claude Code skills — auto-generated from usage_rules config 7. logging-best-practices — external skill for wide events pattern 8. Browser testing — optional GIF-recorded browser walkthrough skill (requires Claude-in-Chrome) 9. Dev environment — optional setup for devenv, flake, or devbox with PostgreSQL

>

Want to customize any of these, or are defaults fine?

If the user says defaults are fine, proceed with all defaults from defaults.md. Default for Domain MCP: yes if Ash domains with resources are detected, no otherwise. Default for Browser testing: no (opt-in only). Default for Dev environment: skip if no config file detected, otherwise default to detected tool.

If the user wants to customize, ask about each piece one at a time:

• Which usage_rules to include (:elixir, :otp, :phoenix, others?)
• Which skills to build (default: ash-framework; suggest others based on detected deps)
• Whether to set up domain MCP (and which domain to wire first)
• Whether to set up browser testing
• Which dev environment tool to use (devenv, flake, or devbox)
• Any additional CLAUDE.md sections

Step 3: Install Dependencies

Known issue: plug dependency conflict

When tidewave (only: :dev) and ash_ai (which brings in ash_json_api) are both present, there is a :only env conflict on the plug dependency. You must add an explicit `plug` dependency to resolve this:

{:plug, "~> 1.19"}

For umbrella projects (root mix.exs):

# Add to deps in root mix.exs
{:plug, "~> 1.19"},
{:usage_rules, "~> 1.2", only: :dev, runtime: false}

Note: The plug dep may not be needed in umbrella projects if tidewave and ash_ai live in separate child apps. Only add it if mix deps.get reports an :only option conflict on plug.

For the web app (or single app) mix.exs:

# Add to deps
{:tidewave, "~> 0.5", only: :dev}

For the core app (or single app) mix.exs:

# Add to deps
{:ash_ai, "~> 0.5"}

For single app projects, all deps in one mix.exs:

{:plug, "~> 1.19"},
{:ash, "~> 3.0"},
{:ash_phoenix, "~> 2.0"},
{:ash_postgres, "~> 2.0"},
{:ash_ai, "~> 0.5"},
{:usage_rules, "~> 1.2", only: :dev, runtime: false},
{:tidewave, "~> 0.5", only: :dev}

Then run:

mix deps.get

Step 4: Configure usage_rules

Add the usage_rules() function and reference it in the project config. See defaults.md for the default configuration. Adapt based on:

• Umbrella vs single app: In umbrella, usage_rules goes in root mix.exs
• Detected deps: If Oban, Req, LangChain etc. are present, suggest additional skill builds
• Skills location: Always .claude/skills

In the project/0 function, add:

# listeners required for usage_rules to auto-regenerate on code changes
listeners: [Phoenix.CodeReloader],
usage_rules: usage_rules()

Step 5: Wire Up MCP Servers

Tidewave

In the web app's endpoint.ex, add the Tidewave plug before the if code_reloading? block:

if Code.ensure_loaded?(Tidewave) do
  plug Tidewave
end

Domain MCP (if Ash domains with resources exist)

The domain MCP requires two pieces. See references/setup-guide.md for full details.

1. Endpoint plug: Add AshAi.Mcp.Dev inside the if code_reloading? block in endpoint.ex, before Phoenix.LiveReloader (per official AshAi docs):

if code_reloading? do
  socket "/phoenix/live_reload/socket", Phoenix.LiveReloader.Socket

  plug AshAi.Mcp.Dev,
    protocol_version_statement: "2024-11-05",
    otp_app: :my_app

  plug Phoenix.LiveReloader
  plug Phoenix.CodeReloader
  plug Phoenix.Ecto.CheckRepoStatus, otp_app: :my_app
end

2. Router scope: Add a /dev/mcp scope inside the if Application.compile_env(:my_app, :dev_routes) guard in router.ex:

scope "/dev/mcp" do
  forward "/", AshAi.Mcp.Router,
    tools: @mcp_tools,
    protocol_version_statement: "2024-11-05",
    otp_app: :my_app,
    actor: %AshAi{}
end

3. Domain tools: Add a tools do block in the Ash domain, and a @mcp_tools module attribute in the router listing exposed tool names. Ask the user which domain to wire first.

If no Ash domains with resources exist yet, skip the domain MCP and just set up Tidewave.

.mcp.json

Create .mcp.json in the project root. Include both servers if domain MCP was set up:

{
  "mcpServers": {
    "tidewave": {
      "type": "http",
      "url": "http://localhost:<port>/tidewave/mcp"
    },
    "<app_name>": {
      "type": "http",
      "url": "http://localhost:<port>/dev/mcp"
    }
  }
}

Replace <port> with the detected Phoenix port (default 4000) and <app_name> with the OTP app name. If domain MCP was skipped, omit the <app_name> entry.

Step 6: Write CLAUDE.md

Write the hand-written sections of CLAUDE.md. See references/setup-guide.md for the full template. The key sections are:

• Ash First — always use Ash concepts, never raw Ecto
• Code Generation — use igniter and Ash generators
• MCP Usage — prefer MCP tools over file reading for app state; use domain MCP to look up resources before writing code
• Umbrella Structure — (if umbrella) which app owns what
• Feedback Loop — compile, format, credo (if installed), test, tidewave eval, domain MCP verify; MCP failure troubleshooting (server not running, 404, empty tools, plug missing)
• Logging — wide events / canonical log lines pattern

Leave space after the hand-written sections for usage_rules to append its generated content.

Step 7: Generate Skills and CLAUDE.md Content

mix usage_rules.sync --yes

Important: The task is usage_rules.sync, not usage_rules.gen. The --yes flag is required for non-interactive execution (otherwise igniter prompts for confirmation on large diffs).

This generates:

• The usage_rules sections appended to CLAUDE.md
• Claude Code skill files in .claude/skills/

Verify the generated files look correct.

Step 8: Install External Skills

npx skills add https://github.com/boristane/agent-skills --skill logging-best-practices --yes

If the user opted in to browser testing:

npx skills add https://github.com/jordangarrison/superpowers --skill browser-testing-walkthrough --yes

Important: The --yes flag is required for non-interactive execution (otherwise it prompts for which agents to install to).

Step 9: Optional — Browser Testing Setup

If the user opted in to browser testing (Step 2), generate a project-specific browser testing skill. The external skill (installed in Step 8) handles the generic workflow; this skill provides project-specific context.

Create .claude/skills/browser-testing/SKILL.md with these sections:

1. Navigation Map — table with Page, URL, Key Elements columns. Pre-fill with

detected routes (at minimum: /, /dev/dashboard, /dev/mailbox). Do not include MCP endpoints (/dev/mcp) — they are not browser-renderable. Use the detected Phoenix port.

1. Seed Data Reference — placeholder: "Fill in your test users and seed data here.

List names, roles, and any notable state (e.g., overallocated users, edge cases)."

1. Tool Quick Reference — condensed cheat sheet: navigate, click, screenshot,

zoom, find, type

1. GIF Budget — 50 frames max, 8-10 per flow, 3-5 flows total
2. PR Comment Template — requires a written summary of what was tested alongside

the GIF embed. Reviewers must understand what was validated without watching the GIF.

See references/setup-guide.md for the full template.

Step 10: Optional — Dev Environment

If the user opted in (or a dev environment config file was detected in Step 1), set up the dev environment. All three options use direnv.

Ask: "Which dev environment tool do you use?" (default to detected tool):

• devenv — devenv.nix + direnv
• flake — flake.nix + direnv
• devbox — devbox.json + direnv

For all options:

1. Generate the appropriate .envrc (see defaults.md for templates)
2. Document required packages: Elixir (>= 1.18), Erlang (>= 27), Node.js, PostgreSQL
3. Note custom PostgreSQL port (5433 to avoid system conflicts)
4. Update config/dev.exs with matching port if needed

Per-option details:

• devenv: Generate .envrc only. Document that the user needs Elixir, Erlang, Node.js, PostgreSQL services in their devenv.nix, and should add dotenv.enable = true for .env support. User looks up devenv-specific syntax.
• flake: Generate .envrc only. Document that the user needs Elixir, Erlang, Node.js, PostgreSQL in their flake outputs. User looks up Nix-specific syntax.
• devbox: Generate full devbox.json, process-compose.yml, and .envrc. See references/setup-guide.md for the complete devbox config with PostgreSQL, init_hook, and convenience scripts.

Step 11: Verify

mix deps.get
mix compile
mix format --check-formatted

Confirm:

• mix compile succeeds
• CLAUDE.md has both hand-written and generated sections (including MCP Usage)
• .claude/skills/ contains generated skill files
• .mcp.json exists with Tidewave config (and domain MCP config if set up)
• Tidewave is accessible when the Phoenix server is running
• (If domain MCP) Domain MCP accessible at /dev/mcp when Phoenix server is running
• (If browser testing) Browser testing skill exists at .claude/skills/browser-testing/SKILL.md
• (If dev environment) .envrc exists with correct content for chosen tool

Report what was set up and any manual steps remaining.