OpenCode Setup with AnonRouter

OpenCode can use AnonRouter as a custom OpenAI-compatible provider. Add one compatibility-enabled key, declare the models you want in opencode.json, and switch among them from OpenCode's /models picker.

Before you begin

You need:

1. A current OpenCode installation.
2. An AnonRouter account with available credits.
3. An inference key with OpenAI-compatible access enabled.
4. At least one tool-capable model id from the AnonRouter catalog.

OpenCode sends a conventional bearer key and cannot perform AnonRouter's two-step private ticket exchange. Use a dedicated compatibility key with a credit limit appropriate for an agent that can make repeated requests.

1. Save the AnonRouter credential

Start OpenCode and run:

/connect

Then:

1. Scroll to Other in the provider list.
2. Enter anonrouter as the provider id.
3. Paste the compatibility-enabled AnonRouter inference key.

The provider id must exactly match the key used in the JSON configuration. OpenCode stores credentials entered through /connect in ~/.local/share/opencode/auth.json.

2. Add the custom provider

Create opencode.json in the project root, or add the provider to the existing file:

{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "anonrouter": {
      "npm": "@ai-sdk/openai-compatible",
      "name": "AnonRouter",
      "options": {
        "baseURL": "https://api.anonrouter.ai/v1"
      },
      "models": {
        "anthropic/claude-opus-4.8": {
          "name": "Claude Opus 4.8"
        },
        "anthropic/claude-sonnet-5": {
          "name": "Claude Sonnet 5"
        },
        "moonshotai/kimi-k2.5": {
          "name": "Kimi K2.5"
        },
        "qwen/qwen-3-coder-480b-turbo": {
          "name": "Qwen 3 Coder 480B"
        }
      }
    }
  }
}

@ai-sdk/openai-compatible tells OpenCode to use the OpenAI Chat Completions protocol. The baseURL must end at /v1; OpenCode adds /chat/completions itself.

The model map is explicit because OpenCode does not automatically import a custom provider's complete catalog. Replace stale examples with exact current ids from AnonRouter. Only include models you want displayed in the picker.

Global or project configuration

OpenCode merges its configuration sources. The most useful locations are:

A project configuration overrides conflicting global settings. OpenCode's official documentation says project configuration is safe to commit, but that assumes it contains no embedded secrets. Keep the API key in /connect storage or an environment variable.

Environment-variable alternative

Instead of /connect, add apiKey under the provider's options:

{
  "options": {
    "baseURL": "https://api.anonrouter.ai/v1",
    "apiKey": "{env:ANONROUTER_API_KEY}"
  }
}

Set the value before starting OpenCode:

export ANONROUTER_API_KEY=ar_REPLACE_WITH_YOUR_API_KEY
opencode

This JSON is only the options fragment; merge it into the complete provider configuration rather than replacing opencode.json with it.

3. Select a model

Restart OpenCode after changing the provider configuration, then run:

/models

Choose a model under AnonRouter. OpenCode identifies custom models as provider_id/model_id; for example, the first configuration entry is selected as:

anonrouter/anthropic/claude-opus-4.8

The portion sent to AnonRouter remains anthropic/claude-opus-4.8.

You can also set a default at the root of opencode.json:

{
  "model": "anonrouter/anthropic/claude-opus-4.8"
}

Choose models for agentic coding

OpenCode notes that coding agents need models that are strong at both code and tool calling. For each AnonRouter route, verify:

• Tools are supported.
• The context window can hold the relevant files, instructions, and tool output.
• The output limit is sufficient for the edits you expect.
• The route's privacy and moderation labels match your project.

Model capabilities and ids change over time. Treat the examples as a starting configuration and verify them against the live catalog before relying on them for unattended work.

How tools work

OpenCode describes local actions—such as reading files, editing code, searching, and running shell commands—with OpenAI tool definitions. AnonRouter forwards supported tool definitions and model tool calls. OpenCode executes the selected tools locally and sends their results back in a later request.

AnonRouter does not execute OpenCode tools. Your OpenCode permissions determine what the agent can read or change, so review them separately from the model provider configuration.

Compatibility limits

Keep the provider package as @ai-sdk/openai-compatible. OpenCode's official guide reserves @ai-sdk/openai for providers using /v1/responses, which is not the AnonRouter endpoint configured here.

Source-code privacy boundary

OpenCode requests may include source files, patches, repository instructions, terminal output, test failures, tool schemas, and earlier conversation context. Anything included in the prompt reaches AnonRouter and the selected model provider.

This setup uses AnonRouter compatibility mode. The compatibility broker temporarily receives key identity and plaintext request together. AnonRouter does not intentionally retain prompts or responses, but this static-key flow is not unlinkable like the native ticket flow.

Use OpenCode's permission controls, exclude secrets and generated artifacts from agent context, and choose an AnonRouter route whose privacy label fits the code you are sending.

Troubleshooting

AnonRouter does not appear under /models

Confirm opencode.json contains the anonrouter provider and at least one entry under models. Saving a credential with /connect does not create the provider configuration by itself.

Authentication returns 401 or 403

Run opencode auth list to confirm the credential is stored under the anonrouter id. Verify the key begins with ar_ and has OpenAI-compatible access enabled.

Requests return 404

Use https://api.anonrouter.ai/v1 for options.baseURL. Do not append /chat/completions.

Model not found

The object key under models must be an exact current AnonRouter API id. Replace stale values with ids from the live catalog and restart OpenCode.

File edits or shell tools do not work

Choose a route that advertises tool calling and review OpenCode's local tool permissions. A successful text response alone does not prove the model emitted a valid tool call.

Context-length errors

Reduce the files and history included in the request or select a model with a larger advertised context window. If you add OpenCode limit fields, copy the current model limits rather than guessing them.

OpenCode setup FAQ

Do I need an OpenCode plugin?

No. OpenCode already supports custom OpenAI-compatible providers.

Can I configure several AnonRouter models?

Yes. Add several entries to the provider's models object, then switch among them with /models.

Should I commit opencode.json?

Project configuration can be committed when it contains only provider and model settings. Keep the key in /connect storage or an environment variable.

Is this AnonRouter's private ticket flow?

No. OpenCode sends a static bearer key and therefore uses compatibility mode.

Sources and further reading

• OpenCode: Providers and custom providers
• OpenCode: Configuration and file locations
• OpenCode: Selecting and configuring models
• AnonRouter compatibility mode
• AnonRouter model catalog

AnonRouter is an independent service and is not affiliated with OpenCode.