Qwen: Qwen3 4b

qwen/qwen3-4b
toolsjsonstreaming
MODALITIES
INPUT PRICE
$0.05per 1M
OUTPUT PRICE
$0.15per 1M
CONTEXT
32.8K
RELEASED

Onlist sends each request to one of these providers. Smart, the default, favors reliability first, then effective price and speed; the higher a provider sits here, the more of the traffic it gets.

ProviderChat
$0.05$0.15
Hit rate
Cache read$0.005

Capabilities

Input modalities
text
Output modalities
text
Features
toolsjson_modestreamingfunction_callingstructured_outputs
1

Get API Key

Create an API key from the Keys page, then set it as an environment variable:

export ONLIST_API_KEY=sk-...
2

Make your first request

Endpoints

POSThttps://onlist.io/v1/chat/completions

OpenAI Chat Completions format

Request Headers
Authorization:Bearer $ONLIST_API_KEY
Content-Type:application/json
Model:qwen/qwen3-4b
POSThttps://onlist.io/v1/responses

OpenAI Responses format

Request Headers
Authorization:Bearer $ONLIST_API_KEY
Content-Type:application/json
Model:qwen/qwen3-4b
POSThttps://onlist.io/v1/messages

Anthropic Messages format

Request Headers
Authorization:Bearer $ONLIST_API_KEY
Content-Type:application/json
Model:qwen/qwen3-4b

Code samples

curl https://onlist.io/v1/chat/completions \
  -H "Authorization: Bearer $ONLIST_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
       "model": "qwen/qwen3-4b",
       "messages": [
         {
           "role": "user",
           "content": "Explain quantum entanglement in one paragraph."
         }
       ]
     }'

Replace $ONLIST_API_KEY with the API key from your Keys page.

Authentication

All requests must include an Authorization: Bearer <TOKEN> header. Generate keys from the Keys page; keys can be scoped to specific models, groups, IP ranges, and rate limits.

3

Enable streaming

Add "stream": true to receive partial responses as server-sent events in real time.

Streaming example

curl https://onlist.io/v1/chat/completions \
  -H "Authorization: Bearer $ONLIST_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
       "model": "qwen/qwen3-4b",
       "messages": [
         {
           "role": "user",
           "content": "Write a haiku about recursion."
         }
       ],
       "stream": true
     }'

Supported parameters

NameTypeDescription
toolsarrayA list of tools the model may call. Currently supports functions.
json_mode
streaming
function_calling
structured_outputs

These are the request parameters this model accepts. Parameter semantics follow the OpenAI Chat Completions specification.