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

Annotations already declare readOnlyHint, idempotentHint and non-destructive, so the safety profile is covered; the description still adds useful operational context by stating the catalog is free and requires no key, and that it is a fixed 84-entry list. It does not describe response envelope shape or pagination, but that is minor for a static catalog.

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 tight sentences: the first front-loads what the catalog is and enumerates its fields, the second states the downstream purpose and the access constraint. No filler and no repetition of the title.

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 carries the burden of describing returns, and it does so by listing every field of a catalog entry including the direction and windows semantics. Together with the annotations and the zero-parameter schema, an agent has everything needed to call it and consume the result.

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 and there is nothing to disambiguate on the input side. The description instead spends its effort documenting the shape of the returned records, which is more valuable here.

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 precisely (the full 84-entry Polyrank metric catalog) and enumerates exactly what each entry contains: id, name, description, category, direction, available windows, advanced flag. An agent knows immediately this is a static reference lookup rather than a computation, which separates it from ranking or reporting siblings.

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 gives a concrete downstream use case: this is the vocabulary for the weights, skill_gates and metric_filters of polyrank_rank_wallets, which tells the agent to call this before configuring a strategy. It does not explicitly exclude or mention the closely related polyrank_get_metric_windows sibling, so the agent must infer which one to use when it only needs window information.

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