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

Beyond the readOnly/idempotent annotations, the description adds concrete behavioral details: it returns top-N relevant tools including names, descriptions, and full input schemas, and states that results are ready to call directly with no second schema lookup. This gives the agent clear expectations of the output format and workflow impact.

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 structured into three purposeful sentences: purpose, usage/domains, and output/usage priority. The domain list is lengthy but informative, and the description avoids unnecessary filler, earning a high score for efficiency.

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 one primary parameter and no output schema, the description accurately covers the input (query), the output (top-N tools with schemas), and the recommended invocation context. It is self-sufficient for an agent to decide when to use it and what to expect.

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?

The input schema already provides 100% coverage for all parameters, including aliases and examples, so the baseline is 3. The description only reiterates 'describing the data or task' for the query parameter and lists example domains, but does not add new semantic detail beyond what the schema already offers.

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 function: 'Find tools by describing the data or task.' It specifies the verb (find) and resource (tools), and lists concrete data domains (SEC filings, FDA drugs, etc.), distinguishing it from sibling tools that perform data searches or analyses rather than tool discovery.

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 implies when not to use it (when you need a direct answer), but does not name specific alternative tools, falling short of the highest benchmark.

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