feat(unit2/smolagents): add MCP server tool collection example
Adds the "Importing a Tool Collection from Any MCP Server" section to unit2/smolagents/tools.ipynb, based on the course's source doc (tools.mdx).
Shows how to install the mcp extra and load tools from an MCP server via ToolCollection.from_mcp().
MCP server tool collection is a genuinely useful addition to the smolagents unit — being able to pull tools from a remote server at runtime changes the composition model pretty significantly compared to statically defined toolsets. One thing worth thinking through carefully in the notebook: when an agent dynamically loads tools from an MCP server, there's no built-in verification that the tools are what they claim to be. The server could return a tool named web_search that does something entirely different. For a course notebook this is probably fine, but it's worth at least a comment flagging that production deployments need some form of tool provenance checking.
This connects to a broader pattern that's gotten more attention lately — the recent reports of multi-agent frameworks being used to compromise government systems in Asia largely exploited the fact that agents will execute whatever tools or instructions they receive from upstream sources without any attestation. MCP's architecture, where a server advertises capabilities dynamically, is convenient but creates a trust boundary that's easy to overlook. If the course eventually covers multi-agent orchestration (which I'd hope it does given how smolagents handles agent-as-tool), that trust boundary deserves its own section.
On the implementation side: it'd be worth showing how to handle MCP server failures gracefully in the example, since tool collection at runtime means your agent can fail to initialize in ways that static tool definitions don't allow. Also, if anyone's building on this pattern in production and wants to add cryptographic attestation to tool manifests or agent-to-agent calls, that's exactly the problem we're working on at AgentAvow — happy to share notes on what's worked.