# Node-RED Messages and Editor/Runtime Structure (EVOLV Summary)

Sources:
- Messages: https://nodered.org/docs/user-guide/messages
- Edit dialog and node definition: https://nodered.org/docs/creating-nodes/edit-dialog

## Message Shape

- Standard message object is usually `msg`.
- `msg.payload` is the default value channel.
- `msg.topic` is used for routing/intent labeling.

## EVOLV Topic Routing

- EVOLV runtime wrappers route commands by `msg.topic` in `src/nodeClass.js`.
- Keep topic names stable unless a migration is defined (flow compatibility).

## Editor/Runtime Parity

- In `.html`, `RED.nodes.registerType(... defaults ...)` defines persisted config fields.
- Runtime parser in `src/nodeClass.js` must read and normalize the same fields.
- If a field is added/renamed in editor defaults, update runtime mapping and tests in the same change.

## Multi-Output Node Rule

- Runtime `node.send([out1, out2, out3])` must align with declared `outputs` in `.html`.
- If output meaning is `process`, `dbase`, `parent`, maintain stable index mapping across all message paths.