Returns a paginated list of UDF definitions.

Deferred Execution

This endpoint supports deferred (asynchronous) execution for large result sets. When enabled, the API queues the request and returns HTTP 202 with a request_id. Results are streamed to S3 and made available via presigned URL.

Query Parameters

• is_async (boolean): Set to true to enable asynchronous processing.
• callback_url (string): Optional HTTPS URL to receive completion notifications. The payload contains request_id, status, and data_url (when available).
• callback_secret (string): Optional secret for HMAC signature verification. Only used when callback_url is provided.

Callback Signature Verification

When callback_secret is provided, deferred callbacks include HMAC signature headers so the receiver can authenticate the sender. The callback request includes X-ERC-Callback-Timestamp and X-ERC-Callback-Signature headers; receivers should verify the signature before trusting the payload.

The signature is HMAC-SHA256 over <timestamp>.<canonical_body> where canonical_body is JSON serialized with stable key ordering and no extra whitespace (equivalent to Python: json.dumps(payload, separators=(',', ':'), sort_keys=True)). Do not compute the HMAC over the raw HTTP body.

Workflow

1. Submit request with is_async=true
2. Receive HTTP 202 with request_id
3. Poll Check Deferred Execution Status API or wait for callback
4. Download results from presigned data_url