Qwen

What it does

Operation

POST /v1/chat/completions — inference, medium latency
OpenAI-compatible chat completions. Price follows the requested model: qwen3.8-flash bills on the DeepSeek tier (same price as deepseek.x402.press), qwen3.8-max bills on the Exclusive tier (highest tier). Additional OpenAI parameters (temperature, max_tokens, top_p, frequency_penalty, presence_penalty, stop, etc.) are forwarded.

Endpoint

https://qwen.x402.press/v1/chat/completions

What a call costs

Measured from the service's own 402 response on 2026-10-30T23:28:43Z — unpaid, first round only, nothing signed or settled. The exact amount is what a fixed call costs and is the price this page publishes; the quoted amount is always returned in the handshake, so a client never has to compute it.

qwen3.8-flash — metered ceiling, bound to the request shape it was measured with.

qwen3.8-max — metered ceiling, bound to the request shape it was measured with.

A ceiling is only meaningful next to the max_tokens it was measured with. On Base, a metered call with max_tokens: 1000 tops out at qwen3.8-flash $0.00875 / qwen3.8-max $0.256125; the same request with no max_tokens authorises the model's whole output allowance and is the right-hand column — a worst case, never a price. Ethereum is two orders dearer because that figure carries the chain's own settle cost, not the model's. Avalanche offers no metered accept, so a call there is always the exact price.

These are exactly the seven chains the handshake answered for qwen; nothing above is a fallback or an estimate.

Start here

Two rounds, no account: send the request, read the 402, sign the amount it quotes, send it again. The first call is free to discover — a client learns the exact price before it pays anything.

curl -sS https://qwen.x402.press/v1/chat/completions \
  -H 'content-type: application/json' \
  -d '{"model": "qwen3.8-flash",
       "max_tokens": 1000,
       "messages": [{"role": "user", "content": "hi"}]}'
# 402 Payment-Required: base64url JSON, one accept per chain and per scheme
# (exact = the fixed price above; upto = the ceiling for that max_tokens)

The full endpoint list, parameters and manifest are on the service's own host: https://qwen.x402.press.

Free endpoints

No payment, no key — the parts a client needs before it decides to pay.

• GET /v1/models — List available models (qwen3.8-flash, qwen3.8-max)
• GET /qwen/feedback — Return the 50 most recent feedback entries
• POST /qwen/feedback — Submit feedback (response_id, rating 1-5, optional comment)
• GET /.well-known/x402.json — machine manifest
• GET /llms.txt — the same offer, written for a model
• GET /health — liveness

For an agent

• /services/qwen/llms.txt — this page as text: price, operation, free endpoints
• /services/qwen.json — the same data, structured, derived from catalog.json
• /catalog.json — every service, every paid operation, every chain price
• /.well-known/x402.json (service) — the service's own manifest, the authority on its endpoints
• Qwen: two model tiers, one endpoint, priced per call over x402 — x402.review, independent long-form