fix(mcp): preserve headers during auth and debug (#31802)

packages/opencode/src/cli/cmd/mcp.ts

@@ -744,6 +744,7 @@ export const McpDebugCommand = effectCmd({
         const response = await fetch(serverConfig.url, {
           method: "POST",
           headers: {
+            ...serverConfig.headers,
             "Content-Type": "application/json",
             Accept: "application/json, text/event-stream",
           },
@@ -792,6 +793,7 @@ export const McpDebugCommand = effectCmd({
           // Try creating transport with auth provider to trigger discovery
           const transport = new StreamableHTTPClientTransport(new URL(serverConfig.url), {
             authProvider,
+            requestInit: serverConfig.headers ? { headers: serverConfig.headers } : undefined,
           })
 
           try {

packages/opencode/src/mcp/index.ts

@@ -741,7 +741,10 @@ export const layer = Layer.effect(
         auth,
       )
 
-      const transport = new StreamableHTTPClientTransport(url, { authProvider })
+      const transport = new StreamableHTTPClientTransport(url, {
+        authProvider,
+        requestInit: mcpConfig.headers ? { headers: mcpConfig.headers } : undefined,
+      })
 
       return yield* Effect.tryPromise({
         try: () => {