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

Annotations already indicate readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is clear. The description adds valuable behavioral context: it returns 'top-N most relevant tools with names, descriptions, and full input schemas (with curated examples)' and emphasizes that results are 'ready to call directly, no second schema lookup needed.' This clarifies the output format and the tool's meta-search purpose 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 four sentences, each earning its place: purpose, when-to-use with domain list, output format, and a prioritization guidance. It is slightly longer than the minimal two-sentence ideal, but the additional sentences deliver distinct, useful information about the tool's behavior and recommended usage.

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?

With no output schema present, the description properly explains return values: 'top-N most relevant tools with names, descriptions, and full input schemas (with curated examples).' It also covers the recommended invocation context. It does not address edge cases like no matches or ambiguous queries, but those are not essential for a discovery tool with a rich parameter schema.

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%, so the schema fully documents all six parameters, including aliases and the limit default. The description adds the example task phrasing ('analyze housing market trends', 'look up FDA drug approvals') but those examples are also present in the schema's examples array. The description does not add meaning beyond the schema, so the baseline 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 clearly states a specific verb and resource: 'Find tools by describing the data or task.' It enumerates a broad set of domains (SEC filings, FDA drugs, economic data, etc.) and distinguishes itself as a meta-tool for discovering other tools, especially compared to sibling tools like search_within or validate_claim.

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 gives explicit when-to-use 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).' It does not explicitly name alternatives or exclusion criteria, but the 'not just one answer' caveat implies when a single known tool might be more appropriate.

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