We shipped a new model router! Use 600+ models from 45 providers with a single API. Plus automatic model fallbacks to keep your apps running when providers have issues.
Release: @mastra/core@0.20.0
Model Router & Automatic Fallbacks
Model Router
We've built a model router that gives you access to 600+ models from 45 providers through simple magic strings. No need to import provider-specific packages or dealing with different SDKs. Just use the "provider/model" pattern and Mastra handles the rest.
1// Use any model with a simple string
2const agent = new Agent({
3 name: "MyAgent",
4 model: "anthropic/claude-3.5-haiku" // Or "openai/gpt-4o", "google/gemini-pro", etc.
5});The router automatically detects API keys from environment variables and provides full TypeScript autocomplete for every model directly in your editor. The playground now includes a searchable model picker that also shows provider connection status and links to documentation.
See PR #8235 and PR #8332 for implementation.
Automatic Model Fallbacks
Define fallback chains to ensure your applications stay online even when providers experience issues. If one model fails, Mastra automatically switches to the next one in your list.
1// Define fallback chains for reliability
2const agent = new Agent({
3 name: "MyAgent",
4 model: ["anthropic/claude-3-opus", "openai/gpt-4o", "google/gemini-pro"]
5});The playground displays which model from your fallback list was successfully used, giving you full visibility into your model routing.
See PR #7427 and PR #8167 for implementation.
New Streaming Architecture is Now Default
Our battle-tested streamVNext and generateVNext functions are now the standard stream and generate. This is a breaking change. If you're already using vNext functions, migration is trivial—just rename them. For those on original functions, Legacy variants preserve the old behavior.
See our full announcement for the complete story behind this.
Other updates from the last week
- LangSmith Observability: New observability package adapted from the Braintrust implementation for enhanced monitoring and tracing. PR #8160
- OpenTelemetry Exporter: Initial release of OpenTelemetry exporter to enable AI observability. PR #8273
- Netlify Gateway Support: Added NetlifyGateway class with dynamic URLs and token generation for enhanced deployment options. PR #8331
- AI SDK Transformer: New workflow transformer for seamless integration with Vercel's useChat hook in React applications. PR #7829
- PostgreSQL SSL Support: Added optional SSL configuration with improved type safety and error handling. PR #8178
For the complete list of changes, check out the full release notes.
That's all for this week!
Happy building! 🚀