Claude Sonnet 4.6

Claude Sonnet 4.6 is Anthropic's most capable Sonnet model, released February 17, 2026, with upgrades across coding, computer use, long-context reasoning, agent planning, knowledge work and design. Per Anthropic, early-access developers preferred it to its predecessor by a wide margin and often even to Claude Opus 4.5, with a 1M-token context window in beta. It became the default model on Anthropic's Free and Pro plans, shows strong resistance to prompt injections, and holds pricing at $3 per million input and $15 per million output tokens. Ideal for cost-efficient agentic work, coding and long-context tasks that previously required an Opus-class model.

curl https://api.tunerouter.com/v1/chat/completions \
  -H "Authorization: Bearer $TUNEROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "claude-sonnet-4-6", "messages": [{"role": "user", "content": "Hello!"}]}'

Model ID: claude-sonnet-4-6 · works with OpenAI SDKs — just point base_url at api.tunerouter.com