MCP client refactor - storage adapter (#652)

* move storage to the client manager

* fix: url missing after page load

* fix: dots

* fix: callback handling is now in client manager with 2 stage storage.

* some auth edge cases

* make storage sync for the moment to reduce complexity

* better default states

* cancel button on frontend

* remove openai from agents package.json

* unify mcp storage

* fix lock file

* fix: tests

* feat: more refactor

* tools tests

* update x402

* fix: types

* update default model in playground

* reasoning card

* Apply suggestion from @mattzcarey

* fix: from review

* add smooth scrolling

* fix: calling restore onstart and json schema the rest of the time

* fix: oauth tests

* remove smooth scroll :(

* make tests smaller

* rename to client for review

* revert changes to mcp.connect()

* make storage async

* fix readonly nit

* revert remove openai ai sdk provider

* remove public storage api

* add todos for ensureJsonSchema

* fix: mcp server states and unify observability to the mcp client manager class.

* remove callback cache

* dead

* createConnection. in memory method

* add tests

* changeset

* formatting

* claude comments

* remove redundant checks

Author: mattzcarey

.changeset/plenty-friends-hope.md

@@ -0,0 +1,24 @@
+---
+"agents": minor
+---
+
+### Breaking Changes
+
+- **`getMcpServers()` is now async**: Changed from synchronous to asynchronous method to support storage operations
+- **`DurableObjectOAuthClientProvider` constructor**: Now accepts `OAuthClientStorage` interface instead of `DurableObjectStorage`
+
+### New Features
+
+- **`MCPClientManager` API changes**:
+  - New `registerServer()` method to register servers (replaces part of `connect()`)
+  - New `connectToServer()` method to establish connection (replaces part of `connect()`)
+  - `connect()` method deprecated (still works for backward compatibility)
+  - Requires `MCPClientStorage` interface implementation (provided via `AgentMCPClientStorage`)
+- **Storage abstraction layer**: New `MCPClientStorage` and `OAuthClientStorage` interfaces enable custom storage implementations beyond Durable Objects
+- **Connection state observability**: New `onServerStateChanged()` event for tracking all server state changes
+- **Improved reconnect logic**: `restoreConnectionsFromStorage()` handles failed connections
+
+### Bug Fixes
+
+- Fixed failed connections not being recreated on restore
+- Fixed redundant storage operations during connection restoration

packages/agents/src/ai-chat-agent.ts

@@ -190,10 +190,12 @@ export class AIChatAgent<Env = unknown, State = unknown> extends Agent<
   override async onRequest(request: Request): Promise<Response> {
     return this._tryCatchChat(() => {
       const url = new URL(request.url);
+
       if (url.pathname.endsWith("/get-messages")) {
         const messages = this._loadMessagesFromDb();
         return Response.json(messages);
       }
+
       return super.onRequest(request);
     });
   }