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

With no annotations, the description must carry the behavioral burden, and it does disclose cost (FREE) and the shape of the payload. It does not state read-only nature, rate limits, or auth requirements, though these risks are minimal for a zero-parameter info endpoint.

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?

A single sentence with the key qualifier (FREE) front-loaded and no filler. It is tight, though the parenthetical could be slightly more structured.

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 zero-parameter, no-output-schema tool, the description sufficiently covers what the call returns (price, directories, invocation guidance). Nothing an agent needs to decide whether to call it is conspicuously absent.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; the baseline for a parameterless tool applies.

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 names the resource (agent directory listing service) and enumerates the content returned: price, directories, and how to call list_me. It implicitly distinguishes itself from the sibling list_me by positioning itself as the metadata/prerequisite tool, though "Info" is a soft verb rather than a crisp action.

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?

"FREE" plus the reference to "how to call list_me" implies this should be consulted before invoking list_me, which is useful routing. However, it never states explicitly when to use this versus list_me or other siblings, so the guidance is inferred rather than stated.

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