Everything our SDKs do goes over the public HTTP and WebSocket API, so you can
call it directly from any language. The base URL, authentication, error shape,
and the list of endpoints are on the API Reference
landing page; this page covers what you need on top of that when you have no SDK.
Keys and the EU endpoint
Send the key as Authorization: Bearer YOUR_API_KEY, X-API-Key, or
?api_key= on WebSocket URLs (see Authentication).
The eu- key prefix is understood only by the SDKs: for the EU endpoint, call
https://api.eu.kugelaudio.com and send the key without the prefix.
Sending text safely
Encode JSON as UTF-8. For predictable normalization of short or ambiguous
text, set language explicitly. Unicode NFC normalization can also make
equivalent composed and decomposed input consistent before it reaches the
API.
wscat
(npm install -g wscat) or websocat:
A refused connection (bad key, connection limit) is an HTTP status on the
upgrade, not a WebSocket close code; see
Error Codes.
Every streaming endpoint page includes complete raw-WebSocket examples in
Python and JavaScript alongside the wire-format tables: start with
Stream Speech for one request at a time or
Stream Input for LLM token streams. Last modified on September 22, 2026
