Synthetic

Synthetic exposes Anthropic-compatible endpoints. OpenClaw registers it as the synthetic provider and uses the Anthropic Messages API.

Quick setup

Set SYNTHETIC_API_KEY (or run the wizard below).
Run onboarding:

openclaw onboard --auth-choice synthetic-api-key

The default model is set to:

synthetic/hf:MiniMaxAI/MiniMax-M2.1

Config example

{
  env: { SYNTHETIC_API_KEY: "sk-..." },
  agents: {
    defaults: {
      model: { primary: "synthetic/hf:MiniMaxAI/MiniMax-M2.1" },
      models: { "synthetic/hf:MiniMaxAI/MiniMax-M2.1": { alias: "MiniMax M2.1" } },
    },
  },
  models: {
    mode: "merge",
    providers: {
      synthetic: {
        baseUrl: "https://api.synthetic.new/anthropic",
        apiKey: "${SYNTHETIC_API_KEY}",
        api: "anthropic-messages",
        models: [
          {
            id: "hf:MiniMaxAI/MiniMax-M2.1",
            name: "MiniMax M2.1",
            reasoning: false,
            input: ["text"],
            cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 },
            contextWindow: 192000,
            maxTokens: 65536,
          },
        ],
      },
    },
  },
}

Note: OpenClaw’s Anthropic client appends /v1 to the base URL, so use https://api.synthetic.new/anthropic (not /anthropic/v1). If Synthetic changes its base URL, override models.providers.synthetic.baseUrl.

Model catalog

All models below use cost 0 (input/output/cache).

Model ID	Context window	Max tokens	Reasoning	Input
`hf:MiniMaxAI/MiniMax-M2.1`	192000	65536	false	text
`hf:moonshotai/Kimi-K2-Thinking`	256000	8192	true	text
`hf:zai-org/GLM-4.7`	198000	128000	false	text
`hf:deepseek-ai/DeepSeek-R1-0528`	128000	8192	false	text
`hf:deepseek-ai/DeepSeek-V3-0324`	128000	8192	false	text
`hf:deepseek-ai/DeepSeek-V3.1`	128000	8192	false	text
`hf:deepseek-ai/DeepSeek-V3.1-Terminus`	128000	8192	false	text
`hf:deepseek-ai/DeepSeek-V3.2`	159000	8192	false	text
`hf:meta-llama/Llama-3.3-70B-Instruct`	128000	8192	false	text
`hf:meta-llama/Llama-4-Maverick-17B-128E-Instruct-FP8`	524000	8192	false	text
`hf:moonshotai/Kimi-K2-Instruct-0905`	256000	8192	false	text
`hf:openai/gpt-oss-120b`	128000	8192	false	text
`hf:Qwen/Qwen3-235B-A22B-Instruct-2507`	256000	8192	false	text
`hf:Qwen/Qwen3-Coder-480B-A35B-Instruct`	256000	8192	false	text
`hf:Qwen/Qwen3-VL-235B-A22B-Instruct`	250000	8192	false	text + image
`hf:zai-org/GLM-4.5`	128000	128000	false	text
`hf:zai-org/GLM-4.6`	198000	128000	false	text
`hf:deepseek-ai/DeepSeek-V3`	128000	8192	false	text
`hf:Qwen/Qwen3-235B-A22B-Thinking-2507`	256000	8192	true	text

Notes

Model refs use synthetic/<modelId>.
If you enable a model allowlist (agents.defaults.models), add every model you plan to use.
See Model providers for provider rules.