Fen Ecosystem

Expert guidance for working in the Mechanic/Fen WoW addon development ecosystem.

The Reload Loop (MANDATORY)

After ANY addon code change, you MUST verify the changes in-game:

Ask the user to /reload in WoW (or trigger via keybinding CTRL+SHIFT+R)
Wait for the user to confirm the reload is complete
Then use the addon.output MCP tool (agent_mode=true) to get errors, tests, and console logs

CRITICAL: Do NOT call addon.output immediately after changes. The timing between reload and SavedVariables sync is unpredictable. Always wait for user confirmation before pulling output.

Ecosystem Components

Component	Purpose	Key Tools
Mechanic	Development hub	`env.status`, `addon.output`, `reload.trigger`
FenCore	Pure logic library	`fencore.catalog`, `fencore.search`, `fencore.info`
FenUI	UI widget library	`Layout`, `Panel`, `Tabs`, `Grid`, `Buttons`
MechanicLib	Bridge library	`RegisterAddon`, `Print`, `RegisterTest`

Essential MCP Tools

Task	MCP Tool
Get Addon Output	`addon.output` (agent_mode=true)
Lint Code	`addon.lint`
Run Tests	`addon.test`
Search APIs	`api.search`
Search FenCore	`fencore.search`
Env Status	`env.status`

AFD Core Principles

Mechanic follows Agent-First Development (AFD) — github.com/Falkicon/afd

Tool-First: All functionality must exist as an MCP tool before being added to any UI.
Structured Results: All tools return predictable JSON schemas with success, data, and error.
Agent Mode: Use agent_mode=true for distilled, AI-optimized output.

Routing Logic