opus-4-5-migration

# Opus 4.5 Migration Guide One-shot migration from Sonnet 4.0, Sonnet 4.5, or Opus 4.1 to Opus 4.5. ## Migration Workflow 1. Search codebase for model strings and API calls 2. Update model strings to Opus 4.5 (see platform-specific strings below) 3. Remove unsupported beta headers 4. Add effort parameter set to `"high"` (see `references/effort.md`) 5. Summarize all changes made 6. Tell the user: "If you encounter any issues with Opus 4.5, let me know and I can help adjust your prompts." ## Model String Updates Identify which platform the codebase uses, then replace model strings accordingly. ### Unsupported Beta Headers Remove the `context-1m-2025-08-07` beta header if present—it is not yet supported with Opus 4.5. Leave a comment noting this: ```python # Note: 1M context beta (context-1m-2025-08-07) not yet supported with Opus 4.5 ``` ### Target Model Strings (Opus 4.5) | Platform | Opus 4.5 Model String | |----------|----------------------| | Anthropic API (1P) | `claude-opus-4-5-20251101` | | AWS Bedrock | `anthropic.claude-opus-4-5-20251101-v1:0` | | Google Vertex AI | `claude-opus-4-5@20251101` | | Azure AI Foundry | `claude-opus-4-5-20251101` | ### Source Model Strings to Replace | Source Model | Anthropic API (1P) | AWS Bedrock | Google Vertex AI | |--------------|-------------------|-------------|------------------| | Sonnet 4.0 | `claude-sonnet-4-20250514` | `anthropic.claude-sonnet-4-20250514-v1:0` | `claude-sonnet-4@20250514` | | Sonnet 4.5 | `claude-so...