Kyle Carberry
acbfb90c30
## Problem When adding an external MCP server with `auth_type=oauth2`, admins currently must manually provide: - `oauth2_client_id` - `oauth2_client_secret` - `oauth2_auth_url` - `oauth2_token_url` This requires the admin to manually register an OAuth2 client with the external MCP server's authorization server first — a friction-heavy process that contradicts the MCP spec's vision of plug-and-play discovery. ## Solution When an admin creates an MCP server config with `auth_type=oauth2` and omits the OAuth2 fields, Coder now automatically discovers and registers credentials following the MCP authorization spec: 1. **Protected Resource Metadata (RFC 9728)** — Fetches `/.well-known/oauth-protected-resource` from the MCP server to discover its authorization server. Falls back to probing the server URL for a `WWW-Authenticate` header with a `resource_metadata` parameter. 2. **Authorization Server Metadata (RFC 8414)** — Fetches `/.well-known/oauth-authorization-server` from the discovered auth server to find all endpoints. 3. **Dynamic Client Registration (RFC 7591)** — Registers Coder as an OAuth2 client at the auth server's registration endpoint, obtaining a `client_id` and `client_secret` automatically. The discovered/generated credentials are stored in the MCP server config, and the existing per-user OAuth2 connect flow works unchanged. ### Backward compatibility - **Manual config still works**: If all three fields (`oauth2_client_id`, `oauth2_auth_url`, `oauth2_token_url`) are provided, the existing behavior is unchanged. - **Partial config is rejected**: Providing some but not all fields returns a clear error explaining the two options. - **Discovery failure is clear**: If auto-discovery fails, the error message explains what went wrong and suggests manual configuration. ## Changes - **New package `coderd/mcpauth`** — Self-contained discovery and DCR logic with no `codersdk` dependency - **Modified `coderd/mcp.go`** — `createMCPServerConfig` handler now attempts auto-discovery when OAuth2 fields are omitted - **Tests** — Unit tests for discovery (happy path, WWW-Authenticate fallback, no registration endpoint, registration failure) and `parseResourceMetadataParam` helper
Coder enables organizations to set up development environments in their public or private cloud infrastructure. Cloud development environments are defined with Terraform, connected through a secure high-speed Wireguard® tunnel, and automatically shut down when not used to save on costs. Coder gives engineering teams the flexibility to use the cloud for workloads most beneficial to them.
- Define cloud development environments in Terraform
- EC2 VMs, Kubernetes Pods, Docker Containers, etc.
- Automatically shutdown idle resources to save on costs
- Onboard developers in seconds instead of days
Quickstart
The most convenient way to try Coder is to install it on your local machine and experiment with provisioning cloud development environments using Docker (works on Linux, macOS, and Windows).
# First, install Coder
curl -L https://coder.com/install.sh | sh
# Start the Coder server (caches data in ~/.cache/coder)
coder server
# Navigate to http://localhost:3000 to create your initial user,
# create a Docker template and provision a workspace
Install
The easiest way to install Coder is to use our
install script for Linux
and macOS. For Windows, use the latest ..._installer.exe file from GitHub
Releases.
curl -L https://coder.com/install.sh | sh
You can run the install script with --dry-run to see the commands that will be used to install without executing them. Run the install script with --help for additional flags.
See install for additional methods.
Once installed, you can start a production deployment with a single command:
# Automatically sets up an external access URL on *.try.coder.app
coder server
# Requires a PostgreSQL instance (version 13 or higher) and external access URL
coder server --postgres-url <url> --access-url <url>
Use coder --help to get a list of flags and environment variables. Use our install guides for a complete walkthrough.
Documentation
Browse our docs here or visit a specific section below:
- Templates: Templates are written in Terraform and describe the infrastructure for workspaces
- Workspaces: Workspaces contain the IDEs, dependencies, and configuration information needed for software development
- IDEs: Connect your existing editor to a workspace
- Administration: Learn how to operate Coder
- Premium: Learn about our paid features built for large teams
Support
Feel free to open an issue if you have questions, run into bugs, or have a feature request.
Join our Discord to provide feedback on in-progress features and chat with the community using Coder!
Integrations
We are always working on new integrations. Please feel free to open an issue and ask for an integration. Contributions are welcome in any official or community repositories.
Official
- VS Code Extension: Open any Coder workspace in VS Code with a single click
- JetBrains Toolbox Plugin: Open any Coder workspace from JetBrains Toolbox with a single click
- JetBrains Gateway Plugin: Open any Coder workspace in JetBrains Gateway with a single click
- Dev Container Builder: Build development environments using
devcontainer.jsonon Docker, Kubernetes, and OpenShift - Coder Registry: Build and extend development environments with common use-cases
- Kubernetes Log Stream: Stream Kubernetes Pod events to the Coder startup logs
- Self-Hosted VS Code Extension Marketplace: A private extension marketplace that works in restricted or airgapped networks integrating with code-server.
- Setup Coder: An action to setup coder CLI in GitHub workflows.
Community
- Provision Coder with Terraform: Provision Coder on Google GKE, Azure AKS, AWS EKS, DigitalOcean DOKS, IBMCloud K8s, OVHCloud K8s, and Scaleway K8s Kapsule with Terraform
- Coder Template GitHub Action: A GitHub Action that updates Coder templates
Contributing
We are always happy to see new contributors to Coder. If you are new to the Coder codebase, we have a guide on how to get started. We'd love to see your contributions!
Hiring
Apply here if you're interested in joining our team.