1# Model Selection Reference
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3Use this reference when choosing or validating Mastra model strings.
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5## Model format
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7Always use `"provider/model-name"` when defining models with Mastra's model router.
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9## Verify provider keys and model names
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11Use the provider registry script to look up available providers and models:
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13```bash
14# List all available providers
15node scripts/provider-registry.mjs --list
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17# List all models for a specific provider, sorted newest first
18node scripts/provider-registry.mjs --provider openai
19node scripts/provider-registry.mjs --provider anthropic
20```
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22When the user asks to use a model or provider, run the script first to verify the provider key and model name are valid. Do not guess model names from memory because they change frequently.
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24If you need examples in a new-project scaffold, see [`create-mastra.md`](create-mastra.md), then verify the chosen model with the provider registry script.
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