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

Annotations already declare the safe read-only, open-world profile. The description adds important behavior beyond annotations: it returns links and typical inputs rather than research data, and the caller must invoke the linked API to get results. It does not describe rate limits, link stability, or error behavior, so it is not fully transparent.

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?

Two short sentences with no wasted wording. The directory purpose and the required follow-up action are front-loaded and easy to parse.

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 directory/router tool with annotations and no output schema, the description gives enough context: it explains the return shape ('links and typical inputs') and the next action ('invoke the linked API'). It omits any explanation of how the 'goal' filter changes results, but the schema covers that parameter.

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 one optional 'goal' parameter is already well documented in the schema, including example values. The description does not mention or add meaning to the 'goal' filter, 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 states a specific verb and resource: 'find the concrete API for a research goal.' It also distinguishes this directory from the sibling research tools by explicitly saying it returns links and typical inputs, and that the linked API must be invoked for actual research data.

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?

It clearly indicates when to use this tool: to locate the concrete API for a research goal, then call the linked API for data. It does not explicitly say when to skip this directory and call a known sibling directly, but the routing guidance is clear.

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