Which models can I migrate from using this skill?

You can migrate from Claude Sonnet 4.0, Sonnet 4.5, or Opus 4.1. Note that Haiku models are specifically excluded from this migration path.

Does this skill work with AWS Bedrock and Google Vertex AI?

Yes, it includes specific target model strings for the Anthropic 1P API, AWS Bedrock, Google Vertex AI, and Azure AI Foundry.

What is the 'effort' parameter mentioned in the guide?

Opus 4.5 supports an 'effort' parameter that can be set to 'high' for complex reasoning tasks, which this skill helps you integrate into your API calls.

Why should I remove the 1M context beta header?

The context-1m-2025-08-07 beta header is not currently supported by Opus 4.5 and will cause errors if left in your API requests.

How does it handle prompt differences in Opus 4.5?

It identifies behavioral shifts like tool over-triggering or 'thinking' sensitivity and provides specific XML-structured prompt adjustments to resolve them upon request.

Claude Opus 4.5 Migration Guide

Name: Claude Opus 4.5 Migration Guide
Author: Activer007

byActiver007

Developer Tools

Migrates codebase model strings and optimizes prompts for the Claude Opus 4.5 transition across major cloud platforms.

About

This skill facilitates the seamless transition of AI-powered applications to the Claude Opus 4.5 model by automating model string updates for Anthropic API, AWS Bedrock, Google Vertex AI, and Azure AI Foundry. It provides intelligent guidance for adjusting system prompts to handle Opus 4.5's specific behavioral nuances, such as its increased responsiveness to instructions, preventing over-engineering, and improving frontend design output. By removing deprecated beta headers and configuring the high-effort parameter, this skill ensures a stable upgrade path while addressing common migration challenges like tool over-triggering and thinking sensitivity.

Key Features

0 GitHub stars
Removal of unsupported 1M context beta headers
Code exploration and anti-over-engineering prompt snippets
Configuration guidance for the high-effort model parameter
Automated model string replacement for multiple cloud providers
Prompt optimization for tool-calling and over-triggering prevention

Use Cases

Resolving over-engineering issues in generated code after a model upgrade
Standardizing multi-cloud model identifiers for Bedrock, Vertex, and Azure
Upgrading production LLM applications from Claude 3.5 Sonnet to 4.5 Opus

About

Key Features

0 GitHub stars
Removal of unsupported 1M context beta headers
Code exploration and anti-over-engineering prompt snippets
Configuration guidance for the high-effort model parameter
Automated model string replacement for multiple cloud providers
Prompt optimization for tool-calling and over-triggering prevention

Use Cases

Resolving over-engineering issues in generated code after a model upgrade
Standardizing multi-cloud model identifiers for Bedrock, Vertex, and Azure
Upgrading production LLM applications from Claude 3.5 Sonnet to 4.5 Opus