Claude Sonnet 5

Anthropic 新一代 Sonnet, 编码 / Agent 性能接近旗舰 opus-4-8 而价格不到一半, 1M 上下文, 高性价比

Model ID: claude-sonnet-5 · Type: chat · Provider: Anthropic

Endpoints: /v1/messages · /v1/chat/completions

Pricing

Input (per 1M tokens)$1.8 USD
Output (per 1M tokens)$9 USD
Cache read (per 1M tokens)$0.18 USD
Cache write 5m (per 1M tokens)$2.25 USD
Cache write 1h (per 1M tokens)$3.6 USD
from openai import OpenAI

client = OpenAI(api_key="sk-...", base_url="https://api.router.ai/v1")
resp = client.chat.completions.create(
    model="claude-sonnet-5",
    messages=[{"role": "user", "content": "Hello"}],
)
print(resp.choices[0].message.content)

FAQ

How much does Claude Sonnet 5 cost on J8API?

Claude Sonnet 5 (`claude-sonnet-5`) is billed per usage at $1.8/1M in · $9/1M out, in USD. Current pricing is always listed at https://j8api.com/models/claude-sonnet-5.

How do I call Claude Sonnet 5 through J8API?

Send a request to https://api.router.ai/v1/v1/messages with the header `Authorization: Bearer <your API key>` and `"model": "claude-sonnet-5"`. The API is OpenAI-compatible, so any OpenAI SDK works by changing base_url to https://api.router.ai/v1 — no other code change.

Which endpoints does Claude Sonnet 5 support?

Claude Sonnet 5 can be called on: /v1/messages; /v1/chat/completions.

What is Claude Sonnet 5's context window?

Claude Sonnet 5 accepts up to 1,000,000 input tokens. Requests exceeding the input limit are rejected before reaching the model.

What can Claude Sonnet 5 do?

Claude Sonnet 5 supports: vision, function_calling, prompt_caching.

Who makes Claude Sonnet 5?

Claude Sonnet 5 is a chat model from Anthropic, available through the J8API gateway with the same API key as every other model.

Call it through the J8API OpenAI-compatible endpoint (API base: https://api.router.ai/v1). AI agents can discover and call every model on this gateway through MCP (https://mcp.router.ai/mcp) with no manual integration.

Which should you pick

API reference · All models