Call events

Receiving URL

Karta sends events to the webhook URL configured for your account. For example:

POST https://your-server.example/webhooks/karta

This is an example customer endpoint, not a Karta API URL. Your application hosts this endpoint; its domain and path depend on your integration. Karta sends a JSON body. Verify its signature and return 200 OK after accepting the event.

Subscription names and delivered event values differ:

Subscription	Delivered `event`
`voice.call.started`	`call_request_received`
`voice.call.ended`	`call_ended`
`voice.call.failed`	`sip_call_failed`
`voice.call.not_connected`	`voice_call_not_connected`
`voice.call.transfer.initiated`	`call_transfer_initiated`
`voice.call.transfer.success`	`call_transfer_success`
`voice.call.transfer.failed`	`call_transfer_failed`
`voice.call.transfer.cancelled`	`call_transfer_cancelled`

Call fields vary by event. Recording and transcript links may be included when available. See Receive call webhooks for signature verification and duplicate handling.

Headers

X-Webhook-Id

string

Delivery identifier. Use it to deduplicate events.

Example:

"a4b83ef05c927d016af3049628cb7e51"

X-Webhook-Timestamp

string

Delivery attempt timestamp, in Unix seconds.

X-Webhook-Signature

string

HMAC-SHA256 signature in the format v1=<hex>. See the receiving guide for verification.

X-Webhook-Signature-Alg

enum<string>

Signature algorithm.

Available options:

HMAC-SHA256

Body

application/json

Call event sent to your configured webhook URL. Call fields vary by event.

string

Delivery identifier, also sent in X-Webhook-Id. Stable across retries for the same event and endpoint.

event

string

Delivered event name. For example, call_ended corresponds to the voice.call.ended subscription.

Example:

"call_ended"

call

object

Call details available for this event. Additional fields may be included.

Show child attributes

Response

200

Event accepted. No response body is required.

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Account

Agents

Calls

Phone numbers

Campaigns

WebSocket sessions

Billing

Webhooks

Call events

Receiving URL

Call events

Headers

Body

Response