docs: acp mcp support (#6491)

documentation/docs/guides/acp-clients.md

@@ -11,7 +11,7 @@ ACP is an emerging specification that enables clients to communicate with AI age
 :::
 
 ## How It Works
-After you configure goose as an agent in the ACP client, you gain access to goose's core agent functionality, including its extensions and tools. 
+After you configure goose as an agent in the ACP client, you gain access to goose's core agent functionality, including its extensions and tools. goose also automatically loads any [configured MCP servers](#using-mcp-servers-from-acp-clients) from your ACP client alongside its own extensions, making their tools available without additional configuration.
 
 The client manages the goose lifecycle automatically, including:
 
@@ -84,6 +84,8 @@ You should now be able to interact with goose directly in Zed. Your ACP sessions
 
 #### Advanced Configuration
 
+##### Overriding Provider and Model
+
 By default, goose will use the provider and model defined in your [configuration file](/docs/guides/config-files). You can override this for specific ACP configurations using the `GOOSE_PROVIDER` and `GOOSE_MODEL` environment variables.
 
 The following Zed settings example configures two goose agent instances. This is useful for:
@@ -111,6 +113,42 @@ The following Zed settings example configures two goose agent instances. This is
 }
 ```
 
+## Using MCP Servers from ACP Clients
+
+MCP servers configured in the ACP client's `context_servers` are automatically available to goose. This allows you to use those MCP servers when using both native client features and the goose agent integration.
+
+**Example (Zed):**
+
+```json
+{
+  "context_servers": {
+    "filesystem": {
+      "command": "npx",
+      "args": [
+        "-y",
+        "@modelcontextprotocol/server-filesystem",
+        "/path/to/allowed/dir"
+      ]
+    }
+  },
+  "agent_servers": {
+    "goose": {
+      "command": "goose",
+      "args": ["acp"],
+      "env": {}
+    }
+  },
+  // more settings
+}
+```
+
+To find out what tools are available, just ask goose while it's running in the client.
+
+:::info
+All MCP servers in `context_servers` are automatically available to goose, provided that they use stdio (command-based) or HTTP transports. goose doesn't support servers that use the deprecated SSE transport.
+
+If a server in `context_servers` has the same name as a goose extension, goose uses its own [configuration](/docs/guides/config-files).
+:::
 ## Additional Resources
 
 import ContentCardCarousel from '@site/src/components/ContentCardCarousel';
@@ -137,4 +175,4 @@ import chooseYourIde from '@site/blog/2025-10-24-intro-to-agent-client-protocol-
       duration: '7 min read'
     }
   ]}
-/>
+/>