fix(mcp): clarify enabledTools filtering semantics

- support both raw and wrapped MCP tool names
- treat [\"*\"] as all tools and [] as no tools
- add warnings, tests, and README docs for enabledTools

README.md

@@ -1112,6 +1112,28 @@ Use `toolTimeout` to override the default 30s per-call timeout for slow servers:
 }
 ```
 
+Use `enabledTools` to register only a subset of tools from an MCP server:
+
+```json
+{
+  "tools": {
+    "mcpServers": {
+      "filesystem": {
+        "command": "npx",
+        "args": ["-y", "@modelcontextprotocol/server-filesystem", "/path/to/dir"],
+        "enabledTools": ["read_file", "mcp_filesystem_write_file"]
+      }
+    }
+  }
+}
+```
+
+`enabledTools` accepts either the raw MCP tool name (for example `read_file`) or the wrapped nanobot tool name (for example `mcp_filesystem_write_file`).
+
+- Omit `enabledTools`, or set it to `["*"]`, to register all tools.
+- Set `enabledTools` to `[]` to register no tools from that server.
+- Set `enabledTools` to a non-empty list of names to register only that subset.
+
 MCP tools are automatically discovered and registered on startup. The LLM can use them alongside built-in tools — no extra configuration needed.