← All Models

Claude Sonnet 5

Anthropic Text

Anthropic's Sonnet-tier flagship — performance close to Opus 4.8 at Sonnet prices, 1M token context, 128k max output, on-by-default adaptive thinking, agentic search and tool use at multiple effort levels.

Web Search Web Fetch Code Execution

Specifications

ProviderAnthropic
CategoryText
Context window1M tokens

Pricing (Starter tier)

390.00 credits / 1M input tokens
1,950.00 credits / 1M output tokens

Higher tiers get volume discounts. See tiers

Quick Start

curl -N https://query.genx.sh/v1/chat/completions \ -H "Authorization: Bearer YOUR_API_KEY" \ -H "Content-Type: application/json" \ -d '{"model":"claude-sonnet-5","messages":[{"role":"user","content":"Refactor this function for clarity and add tests"}],"max_tokens":4096,"stream":true}'

Parameters

NameTypeRequiredDefaultDescription
prompt string required The input text prompt
system_prompt string optional System instructions for the model
max_tokens number optional 128000 Maximum tokens to generate (defaults to the model max, 128k, if omitted)
effort string optional high Reasoning/token effort: low, medium, high, xhigh, or max
image_url string optional URL of an image to analyze
tools array optional Builtin tools: web_search, web_fetch, code_execution

Try Claude Sonnet 5 on GenX Router

Pay only for what you use. No credit card required.