Knowledge base · TOPIC-18

HTTP/2 versus HTTP/1.1 in AI streaming failures

Short answer: the negotiated protocol is diagnostic context. It does not, by itself, explain an interrupted stream.

HTTP semantics are defined independently of protocol version, while RFC 8441 specifies extended CONNECT for bootstrapping WebSocket over HTTP/2. Intermediaries can implement or buffer protocols differently, but correlation between a version and a failure is not proof of causation.

A defensible investigation records the negotiated protocol, certificate validation, first-byte time, interruption time, and whether behavior repeats on one controlled alternate path. Do not force insecure downgrades or probe arbitrary streaming endpoints. Provider documentation should define which tests are safe.

Tivor Open Probe V0.1 does not compare HTTP/1.1 and HTTP/2, measure HTTP/3/QUIC, SSE, or long-lived streams. Its governed OpenAI HTTPS check and short-window samples cover a narrower question; Claude has no approved application-layer HTTPS test in V0.1. Use Open Probe for supported evidence and the Scanner for browser-visible context. Related: WebSocket fails while HTTPS works.