Synthetic

Access 7 Synthetic models through Mastra's model router. Authentication is handled automatically using the SYNTHETIC_API_KEY environment variable.

Learn more in the Synthetic documentation.

.env

SYNTHETIC_API_KEY=your-api-key

src/mastra/agents/my-agent.ts

import { Agent } from "@mastra/core/agent";

const agent = new Agent({
  id: "my-agent",
  name: "My Agent",
  instructions: "You are a helpful assistant",
  model: "synthetic/hf:MiniMaxAI/MiniMax-M3"
});

// Generate a response
const response = await agent.generate("Hello!");

// Stream a response
const stream = await agent.stream("Tell me a story");
for await (const chunk of stream) {
  console.log(chunk);
}

info

Mastra uses the OpenAI-compatible /chat/completions endpoint. Some provider-specific features may not be available. Check the Synthetic documentation for details.

Models

7 available models

Model	Context	Tools	Reasoning	Image	Audio	Video	Input $/1M	Output $/1M
synthetic/hf:MiniMaxAI/MiniMax-M3	524K						$0.60	$1
synthetic/hf:moonshotai/Kimi-K2.7-Code	262K						$0.95	$4
synthetic/hf:nvidia/NVIDIA-Nemotron-3-Super-120B-A12B-NVFP4	262K						$0.30	$1
synthetic/hf:openai/gpt-oss-120b	131K						$0.10	$0.10
synthetic/hf:Qwen/Qwen3.6-27B	262K						$0.45	$4
synthetic/hf:zai-org/GLM-4.7-Flash	197K						$0.10	$0.50
synthetic/hf:zai-org/GLM-5.2	524K						$1	$4

Advanced configuration

Custom headers

src/mastra/agents/my-agent.ts

const agent = new Agent({
  id: "custom-agent",
  name: "custom-agent",
  model: {
    url: "https://api.synthetic.new/openai/v1",
    id: "synthetic/hf:MiniMaxAI/MiniMax-M3",
    apiKey: process.env.SYNTHETIC_API_KEY,
    headers: {
      "X-Custom-Header": "value"
    }
  }
});

Dynamic model selection

src/mastra/agents/my-agent.ts

const agent = new Agent({
  id: "dynamic-agent",
  name: "Dynamic Agent",
  model: ({ requestContext }) => {
    const useAdvanced = requestContext.task === "complex";
    return useAdvanced
      ? "synthetic/hf:zai-org/GLM-5.2"
      : "synthetic/hf:MiniMaxAI/MiniMax-M3";
  }
});