Migration Tiers

The migration scanner (npx flue-eve scan) classifies every file-level Eve pattern into one of four tiers. This tells you what can be migrated automatically vs what needs manual work vs what is incompatible.

Tier breakdown

Tier	Description	Migration
Tier 0	Browser-only code: `useEveAgent`, `eve/client` imports	Zero-touch — Vite aliases handle it
Tier 1	Declarative agent: `agent/instructions.md`, `agent/tools/*.ts`, `eve.config.ts`, simple MCP connections	Auto — scaffold generates Flue modules
Tier 2	`defineTool` / `defineMcpClientConnection` with complex logic, `src/agent/` layout instead of root `agent/`	Warning + manual review
Tier 3	Incompatible: Workflow SDK (`run`, `step`), platform channels, schedules, subagents, `@eve/platform`	Blocked — report explains alternatives

Tier 0 — Zero-touch

These imports are automatically aliased by the Vite plugin:

Eve import	Resolves to
`eve/client`	`flue-eve/client`
`eve/react`	`flue-eve/react`

No code changes needed. Alias is applied when flueEve() is loaded in vite.config.ts.

Tier 1 — Auto-scaffold

Patterns that follow the standard Eve declarative agent layout. The scaffold generates equivalent Flue modules:

agent/instructions.md → inlined into generated Flue agent definition
agent/tools/*.ts → generated Flue tool adapters
agent/connections/*.ts → converted via @flue-eve/connections
eve.config.ts → merged into plugin options

Run npx flue-eve init to generate everything.

Tier 2 — Manual review

These patterns need context-specific decisions:

Pattern	What to do
`defineTool()` with custom wrappers	Rewrite as Flue tool in `src/tools/`
`defineMcpClientConnection` with inline auth	Extract standalone connection definition
`src/agent/` directory layout	Move `agent/` to project root or adjust layout config

Tier 3 — Incompatible

These Eve features have no direct equivalent. Alternatives:

Feature	Alternative
Workflow SDK (`run`, `step`)	Use `@flue-eve/workflows`
Platform channels (`slackChannel`, etc.)	Use Flue `@flue/*` channel integrations
Eve schedules	Use your own scheduler
Subagents	Define separate Flue agents
`@eve/platform`	Use `@flue/runtime` directly

Running the scanner

npx flue-eve scan           # report only
npx flue-eve scan --strict  # fail CI on Tier 2/3
npx flue-eve scan --json    # machine-readable output

Most Eve chat agents are Tier 0/1 — scan first, then npx flue-eve init to scaffold.

See from-eve for the end-to-end migration walkthrough.