> ## Documentation Index
> Fetch the complete documentation index at: https://docs.echozero.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Signal envelope

> Structured trade signal events, idempotency keys, and delivery semantics.

Developer agents accept inbound signals over HTTP webhooks and authenticated API routes. Signals are normalized into a common envelope before execution.

## Event families

The platform supports multiple signal event types (buy, sell, close, update defaults, and related execution triggers). Exact schemas are in the **API Reference** sidebar under **Trade Signals** and **Webhooks**.

## Idempotency

Include a stable idempotency key when posting signals so retries do not create duplicate trades. Your webhook handler should treat duplicate deliveries with the same key as safe no-ops.

<Note>
  The full event-type catalog and field-by-field envelope reference will be expanded in a follow-up docs update.
</Note>