directory

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

No annotations are provided, so the description carries the full burden. It hints at a behavioral trait by labeling the listings '(free)', but does so twice, sloppily, and never states that the operation is read-only, whether it needs auth, or whether results are paginated. For a zero-annotation tool this is a thin behavioral profile.

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?

It is short, but the duplicated '(free) (free)' fragment reads as an editing artifact and wastes the closing slot where scope or usage information should sit. The remaining content is front-loaded enough, but not polished.

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?

With no annotations and no output schema, the description is the only source of information about what the agent gets back, yet it never describes the return shape (e.g. listing objects, categories, pagination). For a simple zero-arg tool it should at minimum say what fields or listing structure the agent can 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 tool takes zero parameters, so the baseline is 4. The description doesn't need to explain parameter syntax, and schema coverage is moot at 100% with an empty object.

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 identifies the resource (a curated DE/EU marketplace of external x402 services returning approved listings) but is a bare noun phrase with no verb, so it's unclear whether the tool fetches, authenticates against, or administers the directory. It also fails to differentiate from the nearby siblings directory_submit, directory_status, and directory_activate, which share the 'directory' namespace.

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?

There is no when-to-use guidance and no mention of alternatives. An agent cannot tell from the text whether this is the lookup step before directory_submit or a separate browsing endpoint, nor under what conditions it should be preferred over service_search.

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