Synthetic

Synthetic exposes Anthropic-compatible endpoints. OpenClaw provides it through the official @openclaw/synthetic-provider plugin and uses the Anthropic Messages API.

Property	Value
Provider	synthetic
Auth	SYNTHETIC_API_KEY
API	Anthropic Messages
Base URL	https://api.synthetic.new/anthropic

Getting started

1. Install the plugin

   openclaw plugins install @openclaw/synthetic-provider
   openclaw gateway restart
   
2. Get an API key

   Get a SYNTHETIC_API_KEY from your Synthetic account, or let onboarding prompt you for one.

3. Run onboarding

   openclaw onboard --auth-choice synthetic-api-key
   
4. Verify the default model

   Onboarding sets the default model to:

   synthetic/hf:MiniMaxAI/MiniMax-M3
   

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

Config example

{
  env: { vars: { SYNTHETIC_API_KEY: "sk-..." } },
  agents: {
    defaults: {
      model: { primary: "synthetic/hf:MiniMaxAI/MiniMax-M3" },
      models: { "synthetic/hf:MiniMaxAI/MiniMax-M3": { alias: "MiniMax M3" } },
    },
  },
  models: {
    mode: "merge",
    providers: {
      synthetic: {
        baseUrl: "https://api.synthetic.new/anthropic",
        apiKey: "${SYNTHETIC_API_KEY}",
        api: "anthropic-messages",
        models: [
          {
            id: "hf:MiniMaxAI/MiniMax-M3",
            name: "MiniMax M3",
            reasoning: true,
            input: ["text", "image"],
            cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 },
            contextWindow: 262144,
            maxTokens: 65536,
          },
        ],
      },
    },
  },
}

Model discovery

With a Synthetic credential, OpenClaw discovers current text models from Synthetic’s /openai/v1/models API. Inference still uses the Anthropic Messages API. Newly advertised models, including small models and syn: aliases, do not need an OpenClaw catalog update.

The live catalog supplies context and output limits, image input, reasoning, tool support, and usage-based token prices. Those prices are estimates, not a subscription bill. See Synthetic’s current model list for availability and its recommended aliases.

Offline catalog generation and unavailable or unusable discovery responses use the bundled seed models. Your selected model is not changed automatically. When you override the inference base URL, OpenClaw skips Synthetic’s fixed discovery URL so a proxy credential is not sent to Synthetic.

Model refs use the form synthetic/<modelId>. Use openclaw models list --provider synthetic to inspect your configured models.

Model allowlist

If you enable a model allowlist (agents.defaults.modelPolicy.allow), add every Synthetic model you plan to use. Models not in the allowlist are hidden from the agent.

Base URL override

If Synthetic changes its API endpoint, override the base URL:

{
  models: {
    providers: {
      synthetic: {
        baseUrl: "https://new-api.synthetic.new/anthropic",
      },
    },
  },
}

OpenClaw still appends /v1 automatically.

Related

Model providers

Provider rules, model refs, and failover behavior.

Configuration reference

Full config schema including provider settings.

Synthetic

Synthetic dashboard and API docs.