OpenCode

Configure the LMU AI API in OpenCode as an OpenAI / Anthropic-compatible backend to use Claude, Codex, GLM, and other models.

Just install OpenCode by following the official docs — the website has a detailed tutorial:

Official docs: https://opencode.ai/docs/

Protocol	`npm`	`baseURL` format	When to use
OpenAI protocol	`@ai-sdk/openai`	Ends in `/v1`, e.g. `https://xxx.com/v1`	GPT, Codex, and most OpenAI-compatible services
Anthropic protocol	`@ai-sdk/anthropic`	Also ends in `/v1`, e.g. `https://xxx.com/v1`	Claude's native protocol, plus Chinese models that declare the Anthropic protocol (such as GLM)

For both the OpenAI and Anthropic protocols, the baseURL must go all the way down to the /v1 level. The SDK only appends the specific endpoint after it (such as /chat/completions or /messages); if you omit /v1, the request is silently dropped — the model returns no error but responds with empty content.

Example 1 — OpenAI protocol

A minimal working config (you can configure multiple models under one provider):

{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "openai": {
      "options": {
        "baseURL": "https://api.lmuai.com/v1"
      },
      "models": {
        "gpt-5.5": { "name": "GPT-5.5" },
        "gpt-5.4": { "name": "GPT-5.4" }
      }
    }
  }
}

Why use `openai` as the provider id?

OpenCode recognizes openai as a built-in provider id, so it automatically loads @ai-sdk/openai and uses the /v1/responses endpoint (with full support for reasoning models). So when connecting to an OpenAI-protocol service, just name the provider id openai and point baseURL at your own gateway — there's no need to write the npm field by hand.

If you need to refine a model's capability declaration (context length, reasoning-effort variants, etc.), just add fields to that model's entry:

"gpt-5.5": {
  "name": "GPT-5.5",
  "limit": { "context": 1050000, "output": 128000 },
  "options": { "store": false },
  "variants": { "low": {}, "medium": {}, "high": {}, "xhigh": {} }
}

Here variants defines the switchable reasoning-effort levels; switch between them at runtime in OpenCode by pressing Ctrl + T.

Example 2 — Anthropic protocol (common for Chinese models)

Some Chinese models (such as GLM) are provided by domestic vendors but follow the Anthropic protocol in their API, so they need @ai-sdk/anthropic:

{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "lmuai": {
      "npm": "@ai-sdk/anthropic",
      "name": "lmuai",
      "options": {
        "baseURL": "https://api.lmuai.com/v1"
      },
      "models": {
        "glm-5.1": {
          "name": "GLM-5.1"
        }
      }
    }
  }
}

How do I tell which protocol it is?

Check the request example in the provider's docs:

Endpoint is /v1/chat/completions → OpenAI protocol
Endpoint is /v1/messages with an anthropic-version request header → Anthropic protocol

Example 3 — Claude native models

To connect a native Claude model (such as claude-sonnet-4-6), the provider id must use the built-in anthropic — you cannot use a custom name:

{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "anthropic": {
      "npm": "@ai-sdk/anthropic",
      "options": {
        "baseURL": "https://api.lmuai.com/v1"
      }
    }
  }
}

Verify:

opencode run --model anthropic/claude-sonnet-4-6 "Hello"

Why can't Claude models use a custom provider id?

Like openai, anthropic is a built-in provider id in OpenCode, and OpenCode ships built-in definitions for the entire Claude model lineup (claude-sonnet-4-6, etc.) under it.

That's why opencode run --model anthropic/claude-sonnet-4-6 "Hello" works; but if you change the provider id to a custom name (such as lmuai/claude-sonnet-4-6), OpenCode can't find the model definition and the test fails.

In short: use anthropic for native Claude models, and only use a custom provider id (such as lmuai) for custom models like GLM.

If you need to use multiple protocols and multiple providers at once, just put them all under provider — they don't interfere with each other. For example, LMU AI offers the GPT series (openai), the Claude series (anthropic), and the GLM series (lmuai, Anthropic protocol) at the same time, and all three providers can share one gateway.

Configure keys

Method 1 — command line (recommended)

# Log in or update the key for a provider
opencode auth login

# List all configured providers and their key status
opencode auth list

# Remove the key for a specific provider
opencode auth logout <provider-name>

Method 2 — edit the config file manually

Add the API key for the relevant provider in ~/.local/share/opencode/auth.json:

{
  "provider-name": {
    "type": "api",
    "key": "your-api-key"
  }
}

Note

The provider name in auth.json must exactly match the provider name in opencode.json.

Don't put apiKey in the options block of opencode.json — OpenCode won't read the key there; it must go through auth.json or opencode auth login.

Verify the config

Once configured, verify quickly with a single command:

opencode run --model provider-name/model-name "Hello"

For example, opencode run --model lmuai/glm-5.1 "Hello". A normal reply means the config works.

If there's no output at all (neither an error nor a reply), it's usually one of these two problems:

The baseURL is missing /v1 — see the tip in the "Choosing a protocol" section above.
The key isn't configured in auth.json — check whether opencode auth list shows the relevant provider.

For more debugging information, add --print-logs --log-level INFO.

Tip

In OpenCode, press Ctrl + T to switch between reasoning-effort levels (variants).

Last updated: 2026-08-26

OpenCode

Configure models

Choosing a protocol