The Architect’s Blueprint: Why Your AI Agent Keeps Picking the Wrong Tool (And How to Fix It)

If your agent keeps picking the wrong tool, stop blaming the model and look at the steering wheel.

Summary: Most agent reliability failures get blamed on the model, but they trace back to architecture: ambiguous tool descriptions, bloated toolsets, unstructured errors, and misclassified MCP primitives. This guide walks through the eight structural decisions that separate fragile demos from production-ready agents, with concrete patterns for tool boundaries, error contracts, tool_choice configuration, and MCP server integration.

Beyond the “Vocabulary Quiz”

In the high-stakes environment of CCA-F Domain 2 (Tool Design and Integration), most developers hit a wall not because of a lack of features, but because of a lack of judgment. You build a sophisticated agentic system, only to watch it…