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

Annotations already declare read-only and idempotent behavior. The description adds valuable behavioral details: it explains that the tool returns top-N relevant tools with full schemas and curated examples, and that results are immediately callable (no second schema lookup). This goes beyond the annotations and sets accurate expectations for the response format.

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?

The description is structured in three sentences, front-loaded with the core purpose. It lists example domains and return characteristics. While slightly longer than minimal, every sentence carries useful information and there is no redundant filler.

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?

The tool has no output schema, but the description clearly explains the return value: top-N tools with names, descriptions, and full input schemas. It also addresses a potential need (no second schema lookup). Given the discovery-related complexity and reasonable length, the description is complete for this context.

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?

Schema coverage is 100% with descriptions for all parameters, including aliases for 'query'. The description reinforces the natural-language intent of the query parameter and mentions 'top-N' aligning with the 'limit' parameter, but the schema already conveys this information. Since the description does not add substantial semantic details beyond the schema, the baseline score of 3 is appropriate.

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?

The description opens with a specific verb+resource: "Find tools by describing the data or task." It clearly differentiates this meta-tool from sibling data-lookup tools by focusing on discovering other tools, listing many domains. No ambiguity about what the tool does.

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?

The description explicitly states when to use the tool: "Use when you need to browse, search, look up, or discover what tools exist." It also adds directive guidance: "Call this FIRST when you have many tools available and want to see the option set," which distinguishes it from directly calling a specific tool. This provides clear usage context.

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