Genesis Docs

Genesis includes a bundled StepFun provider plugin with two provider ids:

  • stepfun for the standard endpoint
  • stepfun-plan for the Step Plan endpoint
Standard and Step Plan are **separate providers** with different endpoints and model ref prefixes (`stepfun/...` vs `stepfun-plan/...`). Use a China key with the `.com` endpoints and a global key with the `.ai` endpoints.

Region and endpoint overview

Endpoint China (.com) Global (.ai)
Standard https://api.stepfun.com/v1 https://api.stepfun.ai/v1
Step Plan https://api.stepfun.com/step_plan/v1 https://api.stepfun.ai/step_plan/v1

Auth env var: STEPFUN_API_KEY

Built-in catalog

Standard (stepfun):

Model ref Context Max output Notes
stepfun/step-3.5-flash 262,144 65,536 Default standard model

Step Plan (stepfun-plan):

Model ref Context Max output Notes
stepfun-plan/step-3.5-flash 262,144 65,536 Default Step Plan model
stepfun-plan/step-3.5-flash-2603 262,144 65,536 Additional Step Plan model

Getting started

Choose your provider surface and follow the setup steps.

Standard

**Best for:** general-purpose use via the standard StepFun endpoint.

Choose your endpoint region

    | Auth choice                      | Endpoint                         | Region        |
    | -------------------------------- | -------------------------------- | ------------- |
    | `stepfun-standard-api-key-intl`  | `https://api.stepfun.ai/v1`     | International |
    | `stepfun-standard-api-key-cn`    | `https://api.stepfun.com/v1`    | China         |

Run onboarding

    ```bash
    genesis onboard --auth-choice stepfun-standard-api-key-intl
    ```

    Or for the China endpoint:

    ```bash
    genesis onboard --auth-choice stepfun-standard-api-key-cn
    ```

Non-interactive alternative

    ```bash
    genesis onboard --auth-choice stepfun-standard-api-key-intl \
      --stepfun-api-key "$STEPFUN_API_KEY"
    ```

Verify models are available

    ```bash
    genesis models list --provider stepfun
    ```
  




### Model refs

- Default model: `stepfun/step-3.5-flash`

Step Plan

**Best for:** Step Plan reasoning endpoint.

Choose your endpoint region

    | Auth choice                  | Endpoint                                | Region        |
    | ---------------------------- | --------------------------------------- | ------------- |
    | `stepfun-plan-api-key-intl`  | `https://api.stepfun.ai/step_plan/v1`  | International |
    | `stepfun-plan-api-key-cn`    | `https://api.stepfun.com/step_plan/v1` | China         |

Run onboarding

    ```bash
    genesis onboard --auth-choice stepfun-plan-api-key-intl
    ```

    Or for the China endpoint:

    ```bash
    genesis onboard --auth-choice stepfun-plan-api-key-cn
    ```

Non-interactive alternative

    ```bash
    genesis onboard --auth-choice stepfun-plan-api-key-intl \
      --stepfun-api-key "$STEPFUN_API_KEY"
    ```

Verify models are available

    ```bash
    genesis models list --provider stepfun-plan
    ```
  




### Model refs

- Default model: `stepfun-plan/step-3.5-flash`
- Alternate model: `stepfun-plan/step-3.5-flash-2603`

Advanced configuration

Full config: Standard provider

```json5
{
  env: { STEPFUN_API_KEY: "your-key" },
  agents: { defaults: { model: { primary: "stepfun/step-3.5-flash" } } },
  models: {
    mode: "merge",
    providers: {
      stepfun: {
        baseUrl: "https://api.stepfun.ai/v1",
        api: "openai-completions",
        apiKey: "${STEPFUN_API_KEY}",
        models: [
          {
            id: "step-3.5-flash",
            name: "Step 3.5 Flash",
            reasoning: true,
            input: ["text"],
            cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 },
            contextWindow: 262144,
            maxTokens: 65536,
          },
        ],
      },
    },
  },
}
```

Full config: Step Plan provider

```json5
{
  env: { STEPFUN_API_KEY: "your-key" },
  agents: { defaults: { model: { primary: "stepfun-plan/step-3.5-flash" } } },
  models: {
    mode: "merge",
    providers: {
      "stepfun-plan": {
        baseUrl: "https://api.stepfun.ai/step_plan/v1",
        api: "openai-completions",
        apiKey: "${STEPFUN_API_KEY}",
        models: [
          {
            id: "step-3.5-flash",
            name: "Step 3.5 Flash",
            reasoning: true,
            input: ["text"],
            cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 },
            contextWindow: 262144,
            maxTokens: 65536,
          },
          {
            id: "step-3.5-flash-2603",
            name: "Step 3.5 Flash 2603",
            reasoning: true,
            input: ["text"],
            cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 },
            contextWindow: 262144,
            maxTokens: 65536,
          },
        ],
      },
    },
  },
}
```

Notes

- The provider is bundled with Genesis, so there is no separate plugin install step.
- `step-3.5-flash-2603` is currently exposed only on `stepfun-plan`.
- A single auth flow writes region-matched profiles for both `stepfun` and `stepfun-plan`, so both surfaces can be discovered together.
- Use `genesis models list` and `genesis models set <provider/model>` to inspect or switch models.
For the broader provider overview, see [Model providers](/concepts/model-providers).

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