Key error diagnosis

StepFun AI | streaming failed

StepFun AI returning 400/502 / streaming failed should not be judged from the message alone. Cross-check key shape, Base URL, balance, model permission, region/IP, and visible model list.

Provider

StepFun AI

China provider route

Error type

streaming failed

medium

Status code

400/502

streaming-failed

Sample models

Step 3.5 Flash

Error route summary

Error type

streaming-failed

medium

Provider

StepFun AI

Status code

400/502

Read-only check. Detection data burns after 5 minutes.

What this error usually means

StepFun AI returning 400/502 / streaming failed should not be judged from the message alone. Cross-check key shape, Base URL, balance, model permission, region/IP, and visible model list.

Provider: StepFun AI
Error type: streaming failed
Status code: 400/502

How to prove it during checking

Read-only check. Detection data burns after 5 minutes.

Run read-only identity first: confirm whether the key really belongs to StepFun AI, not just a compatible protocol.
Then list models or run a lightweight probe: check whether models like Step 3.5 Flash are visible and return stable evidence.
Finally record 400/502, error body, latency, egress IP, and reproducibility to separate balance, permission, route, or upstream issues.

Next action

streaming failed should not only show failed. The console should return the next move: refill balance, change Base URL, switch model, add permission, change egress IP, hold listing, or monitor.

Read-only check. Detection data burns after 5 minutes.
China provider route
Step 3.5 Flash

Open key checker

Read-only check. Detection data burns after 5 minutes.