claude-opus-4-5-migration

To migrate Claude API calls to Opus 4.5, scan your codebase for outdated model strings and prompts, replace them with Opus 4.5 equivalents, remove unsupported beta headers, and add effort configuration. The migration covers prompts, API calls, and configuration files.

Opus 4.5 migration provides platform-agnostic target model strings for Anthropic, AWS Bedrock, Google Vertex AI, and Azure AI Foundry. You replace the older Sonnet 4.x or Opus 4.1 strings in your API calls with these updated Opus 4.5 equivalents.

Yes, you need to adjust prompts when upgrading to Opus 4.5 due to known behavioral differences. The migration process includes reference-guided customization for prompt-snippet and effort guidance to ensure your prompts work correctly with the new model.

No, this Opus 4.5 migration specifically applies to codebases containing prompts and API calls referencing Claude Sonnet 4.x or Opus 4.1. The guidance explicitly avoids Haiku migrations and focuses on updating older Sonnet and Opus versions.

During Opus 4.5 migration, you must remove unsupported beta headers from your API calls and configuration files. The migration process documents these safety and governance changes, adding effort parameters and user-facing notes summarizing the updates.

The Opus 4.5 migration guides updates across platforms and languages by scanning codebases for outdated model strings and prompts, then replacing them with Opus 4.5 equivalents. It provides platform-agnostic mappings and documents all changes with migration references.