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Model Migration Guide
Step-by-step guide to switching between AI providers with minimal disruption
OpenAI (GPT-4o) → Anthropic (Claude Sonnet 4)
OpenAI (GPT-4o) → Google (Gemini 2.5 Pro)
Anthropic (Claude) → OpenAI (GPT-4o)
Any Provider → OpenRouter (Multi-provider)
OpenAI (GPT-4o) → Anthropic (Claude Sonnet 4)
Easy
~1-2 hours
Migration Steps
1
Get Anthropic API key from console.anthropic.com
2
Replace openai SDK with @anthropic-ai/sdk
3
Update message format: role/content structure is similar
4
Replace 'system' message with system parameter
5
Update streaming handler (uses SSE events)
6
Test with existing prompts — most transfer well
API Changes
Endpoint: api.openai.com → api.anthropic.com
Auth: Bearer token → x-api-key header
Model param: gpt-4o → claude-sonnet-4-20250514
Max tokens is required (not optional)