Respond to Webhook

Respond to Webhook (respondToWebhook) sends a custom HTTP response to the caller of a Webhook Trigger. Set the trigger’s When to respond mode to Using a Respond to Webhook step.

At a glanceVerified in app · Oct 29, 2026

Use it to: Return a custom HTTP status code, headers, JSON/text body, or redirect to a waiting Webhook caller
Find it: Tools → Data → Dev tools → Respond to Webhook
Cost: 1 Step credit per execution
Limits: 1 MiB max response body · Caller waits up to 60 seconds
Output: {{ N.statusCode }}, {{ N.headers }}, {{ N.body }}
Instead: Webhook Trigger in When the last step finishes mode (when the final Step's output is the reply)

When the first passing Respond to Webhook Step finishes, Glow sends its status code, headers, and body to the waiting caller immediately. Any Steps after Respond to Webhook continue running in the background.

Webhook (Using a Respond to Webhook step)Lookup or transform dataRespond to WebhookBackground follow-up Steps

Setting it up

Set the Webhook Trigger to wait for this Step

Select your Webhook Trigger at Step 1 and set When to respond (responseMode) to Using a Respond to Webhook step.

Add Respond to Webhook

Open Tools → Data → Dev tools in the dock and select Respond to Webhook. Connect it on the branch that should reply to the caller.

Configure the response

Choose how to reply under Respond with (respondWith):

Option	Value	Fields & behavior
JSON (default)	`"json"`	Sends Body (`body`) as `application/json` (parses JSON text or serializes mapped objects and lists). Set Status code from `200` to `599` (default `200`).
Text	`"text"`	Sends Body as `text/plain; charset=utf-8` (unless you set a custom `Content-Type` header).
Redirect	`"redirect"`	Sends a `Location` header to Redirect URL (`redirectUrl`, must start with `https://`, up to `2,048` characters) with status `301`, `302`, `303`, `307`, or `308` (defaults to `302`).
No body	`"noData"`	Sends status and headers with an empty body (`Status code` `204`, `205`, or `304` also send no body automatically).

Under Optional Props, add up to 50 Headers ({ name, value } pairs). Allowed headers include content-type, cache-control, content-language, etag, last-modified, expires, vary, retry-after, and custom x-* headers. Hop-by-hop, cookie, CORS, and security headers are refused.

Do not return credentials in a webhook response. Workspace secrets and API keys ({{ $secret.* }}, {{ $key.* }}, or sealed variables) are refused with SECRET_IN_UNSAFE_SINK.

What it passes on

The Step records the response it sent so downstream Steps (or your test trace) can inspect it:

Reference	Type	What it holds
`{{ N.statusCode }}`	Number	The HTTP status code sent to the caller (for example `200` or `302`).
`{{ N.headers }}`	Record	Normalized lowercase map of the headers sent with the reply.
`{{ N.body }}`	Text or `null`	The exact response text sent, or `null` for No body and Redirect.

If multiple Respond to Webhook Steps run, the first passing Step sends the HTTP reply. Later executions record their output without overwriting the sent response.

Limits and held-request statuses

Limit or situation	Behavior
Maximum held request wait	60 seconds. If the Step has not run within 60 seconds, the caller receives `504 {"error": "timeout"}` and the run continues in the background.
Maximum response body size	1 MiB (`1,048,576` bytes). Larger bodies fail the reply with `500 {"error": "response_not_sendable"}`.
Run finishes without reaching Respond to Webhook	The caller receives `500 {"error": "no_response"}`.
Run fails before reaching Respond to Webhook	The caller receives `500 {"error": "workflow_failed"}`.
Duplicate `x-glow-correlation-id` on a held webhook mode	Returns `409 {"error": "duplicate"}` immediately without starting a duplicate run.

Examples to copy

Return a JSON lookup

Look up a customer record in a Data Store and return it synchronously as JSON, then log the access in the background:

Set the Webhook Trigger at Step 1 to When to respond: Using a Respond to Webhook step.
Add Data Store → Get a record at Step 2 using {{ 1.body.customerId }}.
Add Respond to Webhook at Step 3 with Respond with: JSON, Status code: 200, and Body:
```
{
  "customerId": "{{ 1.body.customerId }}",
  "profile": "{{ 2 }}"
}
```
Connect a Slack or analytics Step after Step 3. The caller gets the 200 response as soon as Step 3 finishes.

Verify it works

Run: Set the Webhook Trigger to Using a Respond to Webhook step, configure Status code 200 and a JSON body, and run a test
You should see: The Step outputs {{ N.statusCode }}, {{ N.headers }}, and {{ N.body }}, and the test trace records the webhook response.

What’s Next?

Configure signature verification and response modes on the Webhook Trigger.
Make outbound API calls with HTTP Request.