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

Annotations already declare readOnlyHint=true and idempotentHint=true. The description adds context beyond that by stating the return format: 'top-N most relevant tools with names, descriptions, and full input schemas (with curated examples) — each result is ready to call directly, no second schema lookup needed.' This is valuable behavioral disclosure about output and efficiency, and there is 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?

The description is three sentences, front-loaded with the primary purpose. The long list of domains is somewhat verbose but serves to clarify the tool's coverage. Every sentence contributes meaning, and there is no wasted verbiage, but the domain list could be trimmed without losing core 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 discovery tool with no output schema, the description covers the what, when, and return format thoroughly. It explains that results include full schemas and curated examples, making them directly callable, and it clarifies when to invoke it first. Annotations cover safety, and the schema covers parameters, so no critical aspect 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?

Schema description coverage is 100%, with detailed descriptions for all six parameters (including aliases for query and a description for limit). The description itself does not add parameter-level semantics beyond what the schema already provides, but per the rubric, high schema coverage makes a baseline of 3 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 'Find tools by describing the data or task', a specific verb+resource statement. It clearly distinguishes this from sibling tools by positioning it as a meta-tool that returns tool names, descriptions, and schemas, while listing supported domains. This is not a tautology and fully differentiates from siblings.

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 usage context: 'Use when you need to browse, search, look up, or discover what tools exist' and 'Call this FIRST when you have many tools available.' This tells the agent when to use it, and 'Call this FIRST' implies when not to use it (after the option set is known), but it does not name specific alternative tools or state explicit when-not conditions. Thus 4.

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