mirror of
https://github.com/coder/coder.git
synced 2026-06-02 20:48:20 +00:00
Ethan
181e103201
## Problem Coderd can expose an MCP server at `/api/experimental/mcp/http` (we have this enabled on dogfood). Its workspace tools dialed agents through a per-call client-side tailnet stack. Every tool call re-created a WireGuard device, netstack, magicsock + UDP sockets, DERP connection, coordinator websocket, and their goroutines — in a process that already runs a long-lived shared tailnet. The duplicate stacks drove up resource usage under load. ## Fix Route this server's tool calls through the existing shared tailnet, so none of those transports are reconstructed per call. Closing an `AgentConn` now releases a tunnel reference instead of tearing down a transport. ## Potential follow-up `coder exp mcp server` still builds a fresh tailnet per call. It pays per-call latency and causes coordinator/DERP churn. A shared CLI tailnet is more involved — unlike coderd, the CLI has no existing shared tailnet to reuse, so it would need a new long-lived client-side tailnet with reconnect, sleep/wake, and idle-destination handling. There's less motivation to optimize this, given the client-side MCP does not compete for resources with coderd. Closes CODAGT-199 > Generated by mux, but reviewed by a human
65 lines
2.0 KiB
Go
65 lines
2.0 KiB
Go
package coderd
|
|
|
|
import (
|
|
"fmt"
|
|
"net/http"
|
|
|
|
"cdr.dev/slog/v3"
|
|
"github.com/coder/coder/v2/coderd/httpapi"
|
|
"github.com/coder/coder/v2/coderd/httpmw"
|
|
"github.com/coder/coder/v2/coderd/mcp"
|
|
"github.com/coder/coder/v2/codersdk"
|
|
"github.com/coder/coder/v2/codersdk/toolsdk"
|
|
)
|
|
|
|
type MCPToolset string
|
|
|
|
const (
|
|
MCPToolsetStandard MCPToolset = "standard"
|
|
MCPToolsetChatGPT MCPToolset = "chatgpt"
|
|
)
|
|
|
|
// mcpHTTPHandler creates the MCP HTTP transport handler
|
|
// It supports a "toolset" query parameter to select the set of tools to register.
|
|
func (api *API) mcpHTTPHandler() http.Handler {
|
|
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
|
|
// Create MCP server instance for each request
|
|
mcpServer, err := mcp.NewServer(api.Logger.Named("mcp"))
|
|
if err != nil {
|
|
api.Logger.Error(r.Context(), "failed to create MCP server", slog.Error(err))
|
|
httpapi.Write(r.Context(), w, http.StatusInternalServerError, codersdk.Response{
|
|
Message: "MCP server initialization failed",
|
|
})
|
|
return
|
|
}
|
|
// Extract the original session token from the request
|
|
authenticatedClient := codersdk.New(api.AccessURL,
|
|
codersdk.WithSessionToken(httpmw.APITokenFromRequest(r)))
|
|
toolOpt := toolsdk.WithAgentConnFunc(api.agentProvider.AgentConn)
|
|
toolset := MCPToolset(r.URL.Query().Get("toolset"))
|
|
// Default to standard toolset if no toolset is specified.
|
|
if toolset == "" {
|
|
toolset = MCPToolsetStandard
|
|
}
|
|
|
|
switch toolset {
|
|
case MCPToolsetStandard:
|
|
if err := mcpServer.RegisterTools(authenticatedClient, toolOpt); err != nil {
|
|
api.Logger.Warn(r.Context(), "failed to register MCP tools", slog.Error(err))
|
|
}
|
|
case MCPToolsetChatGPT:
|
|
if err := mcpServer.RegisterChatGPTTools(authenticatedClient, toolOpt); err != nil {
|
|
api.Logger.Warn(r.Context(), "failed to register MCP tools", slog.Error(err))
|
|
}
|
|
default:
|
|
httpapi.Write(r.Context(), w, http.StatusBadRequest, codersdk.Response{
|
|
Message: fmt.Sprintf("Invalid toolset: %s", toolset),
|
|
})
|
|
return
|
|
}
|
|
|
|
// Handle the MCP request
|
|
mcpServer.ServeHTTP(w, r)
|
|
})
|
|
}
|