api connection_error ai_generated true

WebSocket handshake failed: 400 Bad Request

ID: api/websocket-handshake-failed

Also available as: JSON · Markdown
80%Fix Rate
84%Confidence
3Evidence
2023-01-01First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
any active — — —

Root Cause

WebSocket upgrade rejected by server or proxy.

generic

Workarounds

  1. 88% success Check proxy supports WebSocket: configure upgrade headers in nginx/ALB
  2. 90% success Verify WebSocket URL uses wss:// for HTTPS endpoints

Dead Ends

Common approaches that don't work:

  1. Fall back to HTTP long-polling permanently 68% fail

    Higher latency and server load

  2. Disable proxy WebSocket checks 75% fail

    May break other traffic