### What this solves
This PR adds support for HTTP and SSE (Server-Sent Events) transports to
Zed's context server implementation, enabling communication with remote
MCP servers. Currently, Zed only supports local MCP servers via stdio
transport. This limitation prevents users from:
- Connecting to cloud-hosted MCP servers
- Using MCP servers running in containers or on remote machines
- Leveraging MCP servers that are designed to work over HTTP/SSE
### Why it's important
The MCP (Model Context Protocol) specification includes HTTP/SSE as
standard transport options, and many MCP server implementations are
being built with these transports in mind. Without this support, Zed
users are limited to a subset of the MCP ecosystem. This is particularly
important for:
- Enterprise users who need to connect to centralized MCP services
- Developers working with MCP servers that require network isolation
- Users wanting to leverage cloud-based context providers (e.g.,
knowledge bases, API integrations)
### Implementation approach
The implementation follows Zed's existing architectural patterns:
- **Transports**: Added `HttpTransport` and `SseTransport` to the
`context_server` crate, built on top of the existing `http_client` crate
- **Async handling**: Uses `gpui::spawn` for network operations instead
of introducing a new Tokio runtime
- **Settings**: Extended `ContextServerSettings` enum with a `Remote`
variant to support URL-based configuration
- **UI**: Updated the agent configuration UI with an "Add Remote Server"
option and dedicated modal for remote server management
### Changes included
- [x] HTTP transport implementation with request/response handling
- [x] SSE transport for server-sent events streaming
- [x] `build_transport` function to construct appropriate transport
based on URL scheme
- [x] Settings system updates to support remote server configuration
- [x] UI updates for adding/editing remote servers
- [x] Unit tests using `FakeHttpClient` for both transports
- [x] Integration tests (WIP)
- [x] Documentation updates (WIP)
### Testing
- Unit tests for both `HttpTransport` and `SseTransport` using mocked
HTTP client
- Manual testing with example MCP servers over HTTP/SSE
- Settings validation and UI interaction testing
### Screenshots/Recordings
[TODO: Add screenshots of the new "Add Remote Server" UI and
configuration modal]
### Example configuration
Users can now configure remote MCP servers in their `settings.json`:
```json
{
"context_servers": {
"my-remote-server": {
"enabled": true,
"url": "http://localhost:3000/mcp"
}
}
}
```
### AI assistance disclosure
I used AI to help with:
- Understanding the MCP protocol specification and how HTTP/SSE
transports should work
- Reviewing Zed's existing patterns for async operations and suggesting
consistent approaches
- Generating boilerplate for test cases
- Debugging SSE streaming issues
All code has been manually reviewed, tested, and adapted to fit Zed's
architecture. The core logic, architectural decisions, and integration
with Zed's systems were done with human understanding of the codebase.
AI was primarily used as a reference tool and for getting unstuck on
specific technical issues.
Release notes:
* You can now configure MCP Servers that connect over HTTP in your
settings file. These are not yet available in the extensions API.
```
{
"context_servers": {
"my-remote-server": {
"enabled": true,
"url": "http://localhost:3000/mcp"
}
}
}
```
---------
Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>