---
title: "Execute an operation DAG"
method: POST
path: "/execute"
tags: ["Execution Engine"]
---

# Execute an operation DAG

`POST /execute`

## Request

- Base URL: `https://api.indexone.io`
- URL: `https://api.indexone.io/execute`
- Auth: API key in header `x-api-key`

Runs an arbitrary operation DAG on the execution engine and returns each operation's output. This is what the workflow builder calls to preview a node graph — nothing is persisted unless the DAG itself contains a persisting operation.

**This route is unauthenticated at the API Gateway** (`AuthorizationType: NONE`, no API key required): it is proxied straight to the workflow service over a VPC link. Treat it accordingly.

Pass `websocket_id` to stream per-node results as they complete over the WebSocket API; the HTTP response still returns the full result, truncated to 20 rows per output. Without it, outputs are returned untruncated.

**The API Gateway integration timeout is 29 seconds.** A DAG that runs longer will have its HTTP connection cut even though the engine keeps going — which is why long runs must use `websocket_id`.

As of 2026-07-21 this endpoint requires a team API key. It was previously reachable without any credential.

## Request body

- object
  - `operations` object[]: The DAG to run.
  - `websocket_id` string: WebSocket connection id to stream node results to. Also accepted as `connection_id`.
  - `team_id` string

## Response `200`

Per-operation results. Outputs are truncated to 20 rows when streaming.

- object

## Other responses

- `400`: No `operations` array in the request body.
- `403`: Missing or invalid API key.
- `422`: The request body failed validation before the DAG was built.
- `500`: The DAG raised. `detail` is the exception message, or `{error, traceback}` when the service runs with tracebacks enabled.

---

[API](https://skmtc.dev/indexone/apis/index-one-rest-api.md) · [All operations](https://skmtc.dev/indexone/apis/index-one-rest-api/llms.txt) · [OpenAPI document](https://skmtc.dev/indexone/apis/index-one-rest-api/revisions/df5a92216a9c?raw)