OpenCode

Overview

OmniMux uses a single gateway Base URL: https://api.omnimux.ai (OpenAI-compatible clients typically use https://api.omnimux.ai/v1). Console: omnimux.ai/dashboard. Model IDs in this guide are examples — confirm with the console or GET /v1/models.

OpenCode is a Go-based open-source command-line programming tool (CLI) that provides powerful AI assistance for developers. It offers an intuitive Terminal User Interface (TUI) and supports multiple LLM providers including OpenAI, Anthropic, Gemini, and more. By integrating OpenCode with OmniMux API, you can access top-tier AI models including Claude, GPT, and Gemini series, enabling unified key multi-model access.

Prerequisites

Before configuring, make sure you have:

1. Terminal Emulator

OpenCode requires a modern terminal emulator. Recommended options:

WezTerm (cross-platform)
Alacritty (cross-platform)
Ghostty (Linux and macOS)
Kitty (Linux and macOS)

Windows users can also use PowerShell or Windows Terminal. macOS users can use the built-in Terminal.app or iTerm2. Linux users can use the built-in terminal or GNOME Terminal, Konsole, etc.

2. Get OmniMux API Key

Log in to OmniMux Console
Find API Keys in the dashboard, click ‘Create New Key’ button, then copy the generated Key
API Key usually starts with sk-

Step 1: Install OpenCode

Tip: If you don’t know how to open a command line terminal, see FAQ - How to open command line terminal The easiest way is through the install script:

curl -fsSL https://opencode.ai/install | bash

Or using Homebrew:

brew install anomalyco/tap/opencode

Windows users should first install Node.js, then install via NPM:

npm i -g opencode-ai@latest

Or using Chocolatey:

choco install opencode

Or using Scoop:

scoop bucket add extras
scoop install extras/opencode

Verify Installation

opencode --version

Success indicator: Shows version information. If you prefer a graphical interface, OpenCode also offers a desktop app available at OpenCode Download Page.

Step 2: Configure OmniMux API

1. Initialize Provider

After installation, run the following command in your terminal before launching OpenCode:

opencode auth login

In the provider list, select other (at the bottom, you can search for it)
Enter Provider ID: type omnimux-anthropic
Enter API Key token: you can enter any value (e.g., admin), the actual key is referenced via config file

This step registers a custom provider in OpenCode’s local credential manager.

2. Edit Config File

Open the OpenCode config directory: Press Win + R, paste the following, then press Enter:

%userprofile%\.config\opencode

In terminal, run:

cd ~/.config/opencode

Or access ~/.config/opencode/ in Finder/file manager Create or edit opencode.json in this directory:

{
"$schema": "https://opencode.ai/config.json",
"provider": {
"omnimux-anthropic": {
"npm": "@ai-sdk/anthropic",
"name": "OmniMux Claude",
"options": {
"baseURL": "https://api.omnimux.ai/v1",
"apiKey": "Your OmniMux API Key"
},
"models": {
"claude-fable-5": {
"name": "Claude Fable 5",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"claude-opus-5": {
"name": "Claude Opus 5",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"claude-opus-4-8": {
"name": "Claude Opus 4.8",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"claude-opus-4-7": {
"name": "Claude Opus 4.7",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"claude-opus-4-6": {
"name": "Claude Opus 4.6",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"claude-sonnet-4-6": {
"name": "Claude Sonnet 4.6",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"claude-sonnet-5": {
"name": "Claude Sonnet 5",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"claude-opus-4-5-20251101": {
"name": "Claude 4.5 Opus",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"claude-sonnet-4-5-20250929": {
"name": "Claude 4.5 Sonnet",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"claude-haiku-4-5-20251001": {
"name": "Claude 4.5 Haiku",
"modalities": { "input": ["text", "image"], "output": ["text"] }
}
}
},
"omnimux-google": {
"npm": "@ai-sdk/google",
"name": "OmniMux Gemini",
"options": {
"baseURL": "https://api.omnimux.ai/v1beta",
"apiKey": "Your OmniMux API Key"
},
"models": {
"gemini-2.5-flash": {
"name": "Gemini 2.5 Flash",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"gemini-2.5-pro": {
"name": "Gemini 2.5 Pro",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"gemini-3-flash-preview": {
"name": "Gemini 3.0 Flash",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"gemini-3-pro-preview": {
"name": "Gemini 3.0 Pro",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"gemini-3.1-flash-lite-preview": {
"name": "Gemini 3.1 Flash Lite",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"gemini-3.1-pro-preview": {
"name": "Gemini 3.1 Pro",
"modalities": { "input": ["text", "image"], "output": ["text"] }
}
}
},
"omnimux-openai": {
"npm": "@ai-sdk/openai",
"name": "OmniMux GPT",
"options": {
"baseURL": "https://api.omnimux.ai/v1",
"apiKey": "Your OmniMux API Key"
},
"models": {
"gpt-5.1": {
"name": "GPT-5.1",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"gpt-5.2": {
"name": "GPT-5.2",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"gpt-5.4": {
"name": "GPT-5.4",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"gpt-5.5": {
"name": "GPT-5.5",
"modalities": { "input": ["text", "image"], "output": ["text"] }
},
"MiniMax-M2.5": {
"name": "MiniMax M2.5",
"modalities": { "input": ["text"], "output": ["text"] }
}
}
}
}
}

⚠️ Important:

Replace "Your OmniMux API Key" with your actual API Key
JSON format is sensitive to symbols

Step 3: Start Using OpenCode

1. Launch OpenCode

After saving the config file, restart your terminal, then navigate to your working directory:

cd your-working-directory

Launch OpenCode:

opencode

2. Verify Configuration

In the chat interface, enter the command:

/models

You should see OmniMux Claude, OmniMux Gemini, and OmniMux GPT in the model list. Select one and you’re ready to go!

FAQ

1. What is OpenCode and what is it used for?

OpenCode is an open-source terminal AI coding assistant with a modern TUI interface. It supports code editing, file operations, and command execution, ideal for AI-assisted programming in terminal environments.

2. How do I verify installation and configuration on first use?

Run these steps in sequence:

opencode --version: Confirm OpenCode is installed
Launch OpenCode and enter /models: Confirm you can see the configured models

3. Where should the config file be placed?

The opencode.json config file should be placed at:

Windows: C:\Users\{username}\.config\opencode\opencode.json
macOS / Linux: ~/.config/opencode/opencode.json

4. What models does OpenCode support?

Through OmniMux API, OpenCode supports the following models: Claude series:

Claude Opus 4.6 / Sonnet 4.6: Latest generation models
Claude 4.5 Opus / Sonnet / Haiku: High-performance model family

Gemini series:

Gemini 2.5 Flash / Pro: Latest generation balanced models
Gemini 3.0 Flash / Pro: Next-generation high-performance models
Gemini 3.1 Flash Lite / Pro: Newest generation models with enhanced capabilities

GPT series:

GPT-5.1 / 5.2 / 5.4 / 5.5: OpenAI latest models
MiniMax M2.5: MiniMax high-performance model

5. How do I switch models?

In the OpenCode interface, enter the /models command, then select your desired model from the list.

6. Why don’t my config changes take effect?

Restart OpenCode
Check opencode.json syntax (JSON format)
Verify config file path is correct

7. What causes 401/403 errors?

401 error: API Key not set or invalid
403 error: Insufficient permissions or expired key
Check the apiKey in your config file

8. Will OpenCode automatically read or upload my local files and code?

OpenCode only reads file content when you explicitly authorize it. It’s recommended to use it in a dedicated project folder.

9. Does OpenCode support Chinese input and output?

Yes, fully supported.

10. What scenarios is OpenCode suited for?

Suited for:

Code writing, debugging, and refactoring
AI-assisted programming in terminal environments
File content analysis and processing
Users who prefer modern TUI interfaces

Not suited for:

Complex GUI interactions
Users unfamiliar with terminal operations

11. How to open command line terminal?

Method 1: Press Win + R, type cmd or powershell, then press Enter
Method 2: Search for “Command Prompt” or “PowerShell” in the Start menu
Method 3: Hold Shift and right-click in a folder, select “Open PowerShell window here”
Method 1: Press Command + Space to open Spotlight, type Terminal, then press Enter
Method 2: Go to “Applications” → “Utilities” → “Terminal”
Method 1: Press Ctrl + Alt + T shortcut
Method 2: Search for “Terminal” in the application menu

Notes

Run OpenCode in a dedicated project folder. Avoid running it in sensitive directories (such as system folders or directories containing credentials). OpenCode operates starting from the current working directory. OpenCode uses JSON format config files. Ensure your config file syntax is correct. You can use online JSON validators to check the format.

Overview

Coding CLIs

Desktop and IDE

OpenClaw

Overview

Prerequisites

1. Terminal Emulator

2. Get OmniMux API Key

Step 1: Install OpenCode

Verify Installation

Step 2: Configure OmniMux API

1. Initialize Provider

2. Edit Config File

Step 3: Start Using OpenCode

1. Launch OpenCode

2. Verify Configuration

FAQ

1. What is OpenCode and what is it used for?

2. How do I verify installation and configuration on first use?

3. Where should the config file be placed?

4. What models does OpenCode support?

5. How do I switch models?

6. Why don’t my config changes take effect?

7. What causes 401/403 errors?

8. Will OpenCode automatically read or upload my local files and code?

9. Does OpenCode support Chinese input and output?

10. What scenarios is OpenCode suited for?

11. How to open command line terminal?

Notes

​Overview

​Prerequisites

​1. Terminal Emulator

​2. Get OmniMux API Key

​Step 1: Install OpenCode

​Verify Installation

​Step 2: Configure OmniMux API

​1. Initialize Provider

​2. Edit Config File

​Step 3: Start Using OpenCode

​1. Launch OpenCode

​2. Verify Configuration

​FAQ

​1. What is OpenCode and what is it used for?

​2. How do I verify installation and configuration on first use?

​3. Where should the config file be placed?

​4. What models does OpenCode support?

​5. How do I switch models?

​6. Why don’t my config changes take effect?

​7. What causes 401/403 errors?

​8. Will OpenCode automatically read or upload my local files and code?

​9. Does OpenCode support Chinese input and output?

​10. What scenarios is OpenCode suited for?

​11. How to open command line terminal?

​Notes

Overview

Prerequisites

1. Terminal Emulator

2. Get OmniMux API Key

Step 1: Install OpenCode

Verify Installation

Step 2: Configure OmniMux API

1. Initialize Provider

2. Edit Config File

Step 3: Start Using OpenCode

1. Launch OpenCode

2. Verify Configuration

FAQ

1. What is OpenCode and what is it used for?

2. How do I verify installation and configuration on first use?

3. Where should the config file be placed?

4. What models does OpenCode support?

5. How do I switch models?

6. Why don’t my config changes take effect?

7. What causes 401/403 errors?

8. Will OpenCode automatically read or upload my local files and code?

9. Does OpenCode support Chinese input and output?

10. What scenarios is OpenCode suited for?

11. How to open command line terminal?

Notes