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

Annotations already declare readOnlyHint=true and idempotentHint=true, so safety is covered. The description adds valuable behavioral context: returns top-N relevant tools, includes full schemas with examples, and 'each result is ready to call directly, no second schema lookup needed.' This goes beyond annotations to describe output format and readiness.

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?

Three sentences, with the main purpose front-loaded. The list of domains is long but purposeful, and the third sentence concisely explains the return value and usage pattern. No fluff, though the domain list could be trimmed without losing value.

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 tool with no output schema, the description fully compensates by explaining the return payload (names, descriptions, schemas, examples), the fact results are callable directly, and the recommended 'first step' usage. The domain list sets clear expectations for coverage. Completeness is high.

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% – all parameters (query, q, task, limit, search, description) have clear descriptions including defaults and aliases. The description's 'top-N' mirrors schema's limit but adds no additional parameter semantics. Baseline 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 uses a specific verb+resource ('Find tools by describing the data or task') and lists many concrete domains (SEC filings, FDA drugs, etc.), distinguishing it from sibling tools by being the discovery/metacategory tool. It also clearly states what it returns (names, descriptions, full input schemas with curated examples), reinforcing purpose.

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?

Explicit guidance: 'Use when you need to browse, search, look up, or discover what tools exist' and 'Call this FIRST when you have many tools available' – gives clear when-to-use instructions and implies the alternative is to directly call a known tool. This strongly frames its place in the workflow.

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