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

Annotations declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is already known. The description adds valuable behavioral context: it returns 'top-N most relevant tools with names, descriptions, and full input schemas (with curated examples)' and states that results are 'ready to call directly, no second schema lookup needed.' This discloses the return format and a key convenience behavior, going beyond the 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?

The description is well-structured but slightly verbose due to the long list of domains. However, each element earns its place: the purpose, use cases, covered domains, return details, and the 'Call this FIRST' directive are all useful. It is front-loaded with the main verb and purpose in the first sentence, so the structure is effective, though it could be tightened 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?

Given that this is a simple discovery tool with no output schema, the description covers the essential aspects: what it does, when to use it, what it returns (top-N tools with schemas), and the fact that results are directly callable. It does not mention error cases or pagination, but for a tool with this low complexity and rich annotations, the description is sufficiently complete for an agent to use it effectively.

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 description coverage is 100% and the schema thoroughly documents each parameter, including aliases and examples for the query field. The description itself does not add parameter-level details beyond restating that the query is a description of the data or task. With full schema coverage, the baseline of 3 is appropriate; the description contributes little additional parameter semantics.

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 clearly states the tool's purpose: 'Find tools by describing the data or task' with a specific verb and resource. It also explicitly lists the domains it covers (SEC filings, financials, FDA drugs, etc.), distinguishing it from all siblings which are domain-specific tools. The phrase 'Call this FIRST' further differentiates it as a discovery meta-tool.

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 provides 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 and want to see the option set (not just one answer).' This gives both affirmative use cases and an explicit exclusion ('not just one answer'), effectively guiding the agent on when to select this tool over direct tools.

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