Anthropic ships 1M-token context (beta) for Claude Sonnet 4

MEDIUM IMPACT update

Developers can now work with up to 1M tokens in Sonnet 4—ideal for large codebases, long PDFs, and multi-file RAG.

What's New

Anthropic launched beta support for a 1,000,000-token context window in Claude Sonnet 4 on its API and Amazon Bedrock.

Key Highlights:

  • 1M-token context available in beta on API & Bedrock.
  • New capacity unlocks long-document and large-repo use cases.
  • API behavior note: some spikes now return HTTP 429 rate_limit_error.

We’ll watch for GA timing, pricing details, and Vertex AI availability.

About Claude

Anthropic's AI assistant focused on safety, accuracy, and helpfulness for analysis, writing, coding, and complex reasoning tasks.