Reilly Wood

Auto-converting existing APIs into MCP tools is problematic because APIs weren't designed for agent constraints like limited context windows and tool counts, and they fail to leverage agents' unique capabilities.

“Referenced in "APIs Don't Make Good MCP Tools"”

Tool calling in LLM-based agents is computationally expensive and context-limited, requiring careful system design to avoid running out of context windows when making multiple sequential calls.

“Wrote about the costs and limitations of tool calling in LLM agents and how tool calls are orders of magnitude more costly than regular function calls.”