Mux
Mux makes it easy to run parallel coding agents, each with its own isolated workspace, from your browser or desktop; it is open source and provider-agnostic. For more background on Mux, see Coder Research.
Mux can be configured to route OpenAI- and Anthropic-compatible traffic through AI Bridge by setting a custom provider base URL and using a Coder-issued token for authentication.
Prerequisites
- AI Bridge is enabled on your Coder deployment.
- A Coder session token or long-lived API key.
Configuration
- Open Mux settings (
Cmd+,/Ctrl+,). - Go to Providers → OpenAI.
- Set API Key to your Coder session token.
- Set Base URL to
https://coder.example.com/api/v2/aibridge/openai/v1.
Replace coder.example.com with your Coder deployment URL.
Environment variables
Mux reads provider configuration from its settings UI and also from environment variables. Environment variables are useful in CI or when running Mux inside a Coder workspace.
Note
Mux treats environment variables as a fallback when a provider is not configured in settings. If you have already configured a provider in the UI, clear it (or update it) for env vars to take effect.
# OpenAI-compatible traffic (GPT, Codex, etc.)
export OPENAI_API_KEY="<your-coder-session-token>"
export OPENAI_BASE_URL="https://coder.example.com/api/v2/aibridge/openai/v1"
# Anthropic-compatible traffic (Claude, etc.)
export ANTHROPIC_API_KEY="<your-coder-session-token>"
export ANTHROPIC_BASE_URL="https://coder.example.com/api/v2/aibridge/anthropic"
Running Mux in a Coder workspace
If you want to run Mux inside a Coder workspace (for example, as a Coder app), you can install it with the Mux module and pre-configure AI Bridge via environment variables on the agent:
data "coder_workspace" "me" {}
data "coder_workspace_owner" "me" {}
resource "coder_agent" "main" {
# ... other agent configuration
env = {
OPENAI_API_KEY = data.coder_workspace_owner.me.session_token
OPENAI_BASE_URL = "${data.coder_workspace.me.access_url}/api/v2/aibridge/openai/v1"
ANTHROPIC_API_KEY = data.coder_workspace_owner.me.session_token
ANTHROPIC_BASE_URL = "${data.coder_workspace.me.access_url}/api/v2/aibridge/anthropic"
}
}
module "mux" {
source = "registry.coder.com/coder/mux/coder"
version = "~> 1.0" # See the module page for the latest version.
agent_id = coder_agent.main.id
}
Advanced: providers.jsonc
If you prefer a file-based config, edit ~/.mux/providers.jsonc:
{
"openai": {
"apiKey": "<your-coder-session-token>",
"baseUrl": "https://coder.example.com/api/v2/aibridge/openai/v1"
},
"anthropic": {
"apiKey": "<your-coder-session-token>",
"baseUrl": "https://coder.example.com/api/v2/aibridge/anthropic"
}
}
References: Mux provider environment variables