| Signal | Result | Reference |
|---|---|---|
| Tokenizer signature | Not measured | – |
| API surface | No other entry shares this exact contract | api_cce6f7c3 |
| Context and output | 1,000,000 context · 64,000 max output | declared |
| Reasoning contract | Optional | declared |
| Serving providers observed | None recorded yet | – |
Claude Sonnet 4 significantly enhances the capabilities of its predecessor, Sonnet 3.7, excelling in both coding and reasoning tasks with improved precision and controllability. Achieving state-of-the-art performance on SWE-bench (72.7%),...
Supported parameters
include_reasoningmax_tokensreasoningstoptemperaturetool_choicetoolstop_ktop_p
defaults: {"temperature":null,"top_p":null,"top_k":null,"frequency_penalty":null,"presence_penalty":null,"repetition_penalty":null}
Cite this page as the evidence record for Anthropic: Claude Sonnet 4: the URL is stable, measurements are dated, and revisions append to the history above. Method: tokenizer fingerprinting, v1, 50 strings.
