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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds valuable behavioral context beyond annotations: it explains the return format ('top-N most relevant tools with names, descriptions, and full input schemas'), notes that results are 'ready to call directly,' and clarifies there is no need for a second schema lookup.

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 and front-loaded with the core purpose. The domain list is somewhat long but directly informs the user of coverage, and every sentence contributes either usage context, output details, or strategic guidance. No sentences are wasted, though it could be tightened.

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?

There is no output schema, so the description correctly takes on the burden of explaining return values: it specifies that the result includes names, descriptions, and full input schemas, and that it is immediately callable. The description also covers the broad domain space and usage strategy, making it complete for a discovery tool.

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%, so the schema fully describes all parameters and aliases. The description adds little beyond saying the query is a 'natural language description' and that the tool returns 'top-N' results, which aligns with the limit parameter but does not introduce new semantic detail.

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 begins with 'Find tools by describing the data or task,' using a specific verb and resource. It clearly distinguishes itself from sibling tools by positioning itself as a tool-discovery meta-tool, and it lists numerous domains and explains the output format, leaving no ambiguity about its function.

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 it: 'Use when you need to browse, search, look up, or discover what tools exist' and 'Call this FIRST when you have many tools available.' It also implies a when-not ('not just one answer'), though it does not name specific alternative tools, so it falls short of a 5.

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