How does this skill handle behavioral differences in Opus 4.5?

It includes specific guidelines to soften tool-triggering language and adds specialized snippets to prevent the model from over-engineering or skipping code inspection.

Which cloud platforms are covered by the model string updates?

The skill provides specific target strings for the Anthropic API, AWS Bedrock, Google Vertex AI, and Azure AI Foundry.

Will it automatically change my system prompts?

Model strings are updated automatically, but behavioral prompt adjustments are only applied if the user explicitly requests them or reports specific issues.

Does this skill support Haiku models?

No, this migration skill is specifically designed for Sonnet 4.0/4.5 and Opus 4.1 to Opus 4.5 transitions; it explicitly excludes Haiku 4.5 migration.

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

Opus 4.5 supports an 'effort' parameter which, when set to 'high', helps the model manage complex reasoning tasks more effectively.

Claude Opus 4.5 Migration Guide

Name: Claude Opus 4.5 Migration Guide
Author: Microck

byMicrock

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API Development

Automates the migration of model strings, API calls, and prompts from legacy Claude models to Opus 4.5.

About

This skill provides a structured workflow for upgrading existing Claude-powered applications to the Opus 4.5 model. It handles the replacement of model strings across multiple platforms including the Anthropic API, AWS Bedrock, Google Vertex AI, and Azure AI Foundry. Beyond simple string replacement, the skill manages the removal of unsupported beta headers, configures optimal effort parameters, and provides targeted prompt engineering snippets to mitigate specific behavioral changes such as tool overtriggering, over-engineering, and code exploration passivity.

Key Features

Effort parameter configuration for high-complexity tasks
Optimization for frontend design quality and code exploration
89 GitHub stars
Automated removal of unsupported 1M context beta headers
Prompt tuning to prevent tool overtriggering and over-engineering
Multi-platform model string updates for Anthropic, AWS, Google, and Azure

Use Cases

Upgrading enterprise backend LLM integrations from Sonnet 4.0 to Opus 4.5
Refining system prompts to handle Opus 4.5 behavioral shifts
Migrating multi-cloud Claude deployments on Bedrock or Vertex AI

About

Key Features

Effort parameter configuration for high-complexity tasks
Optimization for frontend design quality and code exploration
89 GitHub stars
Automated removal of unsupported 1M context beta headers
Prompt tuning to prevent tool overtriggering and over-engineering
Multi-platform model string updates for Anthropic, AWS, Google, and Azure

Use Cases

Upgrading enterprise backend LLM integrations from Sonnet 4.0 to Opus 4.5
Refining system prompts to handle Opus 4.5 behavioral shifts
Migrating multi-cloud Claude deployments on Bedrock or Vertex AI