Build an Ad Library URL

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly, idempotent, and non-destructive. The description adds the key behavioral nuance that this tool builds a URL for independent browser verification rather than performing the search itself or returning ad data. No contradiction with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, no filler: the first states the action and output, the second provides a practical trigger. The most important content is front-loaded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple URL-builder with readOnly annotations, an output schema, and all parameters optional, the description fully covers what the tool does, why it exists, and when it should be used. Nothing essential is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Description only refers generically to 'a set of filters' and gives no parameter-specific semantic help. Schema descriptions cover only three of five parameters, and the description doesn't compensate for the undocumented media_type and active_status semantics beyond their enum values.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Description uses a specific verb ('Turn'), a clear object ('a set of filters'), and a concrete deliverable ('public Ad Library URL'). It distinguishes itself from sibling data-returning tools by emphasising browser-verifiable output rather than ad records or search results.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It explicitly states when the tool is useful: when a search returns empty and the user needs to distinguish 'no results' from 'blocked'. It does not name alternative tools, but the use case is concrete enough for an agent to select it.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.