Lesson 2.1Lesson 8 of 30

Tool interfaces and descriptions

Design effective tool interfaces with clear descriptions and boundaries

Key points

1The model picks a tool mostly by its description. A one-line description makes the choice a guess.
2A good description says what the tool does, its input format with an example query, edge cases, and when to use it instead of a similar tool.
3Two tools with overlapping descriptions get mixed up. Rename them and rewrite both descriptions so their boundaries don't overlap.
4Split a generic do-everything tool into purpose-specific tools with clear contracts.
5Check the system prompt too: a keyword there ("always look up the order first") can pull the model toward the wrong tool despite good descriptions.

What the exam guide checks here

Objective wording from the exam guide (English).

2.1.K1Tool descriptions are the primary mechanism for tool selection; minimal descriptions make selection unreliable
2.1.K2Descriptions should include input formats, example queries, edge cases, boundaries
2.1.K3Ambiguous or overlapping descriptions cause misrouting
2.1.K4Keyword-sensitive system prompt wording can create unintended tool associations
2.1.S1Write descriptions that differentiate purpose, inputs, outputs and when to use vs alternatives
2.1.S2Rename tools and rewrite descriptions to remove overlap
2.1.S3Split generic tools into purpose-specific tools with defined contracts
2.1.S4Review system prompts for keyword-sensitive instructions overriding good descriptions

Answer scenario questions on this topic. Every option comes with an explanation.