Use Modellix LLM with OpenClaw 🦞

Configure OpenClaw to call the Modellix LLM gateway. OpenClaw does not ship a built-in Modellix provider, so add a custom provider that points at Chat Completions on POST /v1/chat/completions.

This page covers LLM text only (https://llm.modellix.ai). For OpenClaw media skills and plugins (image, video, speech), see Plugin and Skill.Modellix model IDs are provider/name (for example openai/gpt-5.5). In OpenClaw, register that full string under your custom provider, then select modellix/<model-id> (for example modellix/openai/gpt-5.5). See Models & Pricing.

Set Up OpenClaw

Get a Modellix API Key

Create a Modellix API key in the console and store it securely. You will set it as MODELLIX_API_KEY in the OpenClaw config below.

Add a Custom Provider

Create or update ~/.openclaw/openclaw.json with a full config that defines the Modellix provider, models, and a primary agent model:

{
  "env": {
    "MODELLIX_API_KEY": "mdlx-xxxxxxxx"
  },
  "models": {
    "mode": "merge",
    "providers": {
      "modellix": {
        "baseUrl": "https://llm.modellix.ai/v1",
        "apiKey": "${MODELLIX_API_KEY}",
        "api": "openai-completions",
        "models": [
          { "id": "openai/gpt-5.5", "name": "GPT 5.5" },
          { "id": "openai/gpt-5.6-sol", "name": "GPT 5.6 Sol" },
          { "id": "openai/gpt-5.6-terra", "name": "GPT 5.6 Terra" },
          { "id": "openai/gpt-5.6-luna", "name": "GPT 5.6 Luna" },
          { "id": "anthropic/claude-sonnet-5", "name": "Claude Sonnet 5" },
          { "id": "google/gemini-3.6-flash", "name": "Gemini 3.6 Flash" },
          { "id": "xai/grok-4.5", "name": "Grok 4.5" }
        ]
      }
    }
  },
  "agents": {
    "defaults": {
      "model": {
        "primary": "modellix/openai/gpt-5.5"
      },
      "models": {
        "modellix/openai/gpt-5.5": {}
      }
    }
  }
}

Replace mdlx-xxxxxxxx with your Modellix API key. Merge these fields into an existing config if you already use OpenClaw.

Field	Value
`Provider ID`	`modellix` (custom; do not use built-in `openai` or `anthropic`)
`baseUrl`	`https://llm.modellix.ai/v1`
`api`	`openai-completions`
`apiKey`	`${MODELLIX_API_KEY}` (or your key string)
`models[].id`	Exact Modellix Model IDs (`provider/name`)
`agents.defaults.model.primary`	`modellix/<model-id>`

Use a custom provider key such as modellix. Overwriting OpenClaw’s built-in openai or anthropic providers sends traffic to the vendor endpoints instead of Modellix.

Add or remove entries under models.providers.modellix.models as needed. Full catalog: Models & Pricing.

Set the Primary Model

The example above sets the primary model to modellix/openai/gpt-5.5. To switch models, update both fields:

agents.defaults.model.primary — OpenClaw ref: modellix/ + Modellix Model ID
agents.defaults.models — include the same ref so the agent can use it

Examples:

Modellix Model ID	OpenClaw primary
`openai/gpt-5.5`	`modellix/openai/gpt-5.5`
`anthropic/claude-sonnet-5`	`modellix/anthropic/claude-sonnet-5`
`google/gemini-3.6-flash`	`modellix/google/gemini-3.6-flash`

You do not need a separate Anthropic base URL for OpenClaw. Register anthropic/... and google/... IDs on the same Modellix custom provider; traffic goes through OpenAI-compatible Chat Completions on https://llm.modellix.ai/v1.

Do not set agents.defaults.model.primary to a built-in ref such as openai/gpt-5.5. That routes through OpenClaw’s native OpenAI provider, not Modellix.

Start OpenClaw

Start or restart the OpenClaw gateway so it loads the updated config:

openclaw gateway run

Optionally list models to confirm Modellix entries appear:

openclaw models list

Troubleshooting

Symptom	Check
401 / auth errors	`MODELLIX_API_KEY` is a valid Modellix key; `${MODELLIX_API_KEY}` resolves in config
Model not found / 404	`models[].id` is a full ID like `openai/gpt-5.5`, not bare `gpt-5.5`; ID is in the live catalog
Traffic hits OpenAI, not Modellix	Primary uses `modellix/...`, not built-in `openai/...`; provider key is `modellix`
Wrong path / URL errors	`baseUrl` is `https://llm.modellix.ai/v1` (include `/v1`), not the media API host
Model ignored by agent	Add the OpenClaw ref under both `models.providers.modellix.models` and `agents.defaults.models`

OpenClaw model providers — custom provider reference
Models & Pricing — Model IDs and rates
LLM API guide — protocols and curl examples
OpenCode — another OpenAI-compatible custom provider setup
Plugin · Skill — OpenClaw media capabilities

Get Started

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Use Modellix LLM with OpenClaw 🦞

Set Up OpenClaw

Troubleshooting

​Set Up OpenClaw

​Troubleshooting

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Set Up OpenClaw

Troubleshooting

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