feat: enums connection state and standardise tool discovery

.changeset/smooth-rats-sink.md

@@ -0,0 +1,17 @@
+---
+"agents": patch
+---
+
+### Breaking
+
+- ClientConnection.init() no long tries discovery automatically. That should be done from the MCPCLientManager after explicitely setting the server to "discovering"
+
+### Features
+
+- New discoverIfConnected() function on MCPClientManager which allows for simpler discover of my capabilities per server.
+
+### Fixes
+
+- MCP Client Discovery failures now throw errors immediately instead of continuing with empty arrays
+- Added new "connected" MCP Connection State to use for a connected server with no tools loaded
+- Created the enum MCPConnectionState to formalise possible states

packages/agents/src/index.ts

@@ -1449,10 +1449,11 @@ export class Agent<
       }
     });
 
-    // Connect to server (updates storage with auth URL if OAuth)
-    // This fires onServerStateChanged event which triggers broadcast
     const result = await this.mcp.connectToServer(id);
 
+    // If state is connected then this is an non oauth connection and we should try discovery.
+    await this.mcp.discoverIfConnected(id);
+
     return {
       id,
       authUrl: result.state === "authenticating" ? result.authUrl : undefined
@@ -1538,21 +1539,16 @@ export class Agent<
 
     // If auth was successful, establish the connection in the background
     if (result.authSuccess) {
-      this.broadcastMcpServers();
-
-      this.mcp
-        .establishConnection(result.serverId)
-        .catch((error) => {
-          console.error(
-            "[Agent handleMcpOAuthCallback] Connection establishment failed:",
-            error
-          );
-        })
-        .finally(() => {
-          this.broadcastMcpServers();
-        });
+      this.mcp.establishConnection(result.serverId).catch((error) => {
+        console.error(
+          "[Agent handleMcpOAuthCallback] Connection establishment failed:",
+          error
+        );
+      });
     }
 
+    this.broadcastMcpServers();
+
     // Return the HTTP response for the OAuth callback
     return this.handleOAuthCallbackResponse(result, request);
   }