Anthropic releases Claude Opus 5

On July 24, 2026 Anthropic announced Claude Opus 5 and said it was available that day on all platforms, with the API model ID claude-opus-5. Anthropic's release notes say the model supports a 1M token context window and 128k max output tokens, is available on the Claude API, Amazon Bedrock, Claude Platform on AWS, Google Cloud, and Microsoft Foundry, and allows thinking to be disabled only at effort high or below, a breaking change from Claude Opus 4.8. The announcement says requests flagged by its cybersecurity classifiers in Claude.ai, Claude Code, and Claude Cowork fall back to Opus 4.8 by default, and it introduced two updates in beta: mid-conversation tool changes on the Claude Platform and automatic fallbacks on the API. Opus 5 is a hosted model; the announcement does not describe a release of weights. USASI has not tested it.12

USASI. (2026, October 13). Anthropic releases Claude Opus 5. United States of America Superintelligence. https://unitedstatesofamericasuperintelligence.com/news/anthropic-releases-claude-opus-5/

@misc{usasi_news_anthropic_releases_claude_opus_5,
  author = {{USASI}},
  title = {Anthropic releases Claude Opus 5},
  year = {2026},
  month = oct,
  howpublished = {\url{https://unitedstatesofamericasuperintelligence.com/news/anthropic-releases-claude-opus-5/}},
  note = {United States of America Superintelligence. Last updated 2026-10-13}
}