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

Beyond the readOnly/openWorld/destructive annotations, the description discloses pagination granularity (20 per page), the ranking criterion, the authoritative data source, that no connection is required, and a prompt-injection warning that fan-written names and handles must be treated as data. That is materially more context than the annotations provide.

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 dense sentence with the resource and scope front-loaded, followed by the safety caveat. No filler, and every clause adds information an agent can act on.

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 an output schema and annotations already present, most burdens are lifted, and the description covers ranking, paging, and injection safety well. The omission of any meaning for the 'query' parameter is the notable gap for a tool whose schema documents nothing.

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 0%, so the description must carry both parameters. It partially covers 'page' via the '20 fans a page' hint but never mentions the 'query' parameter or that it presumably filters by fan name/handle, leaving one of two parameters unexplained.

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 a specific resource ('public fan leaderboard'), its data source ('same data as /api/leaderboard'), its page size, and its ranking rule ('ranked by certified Digger tickets'). The word 'public' implicitly separates it from personal-record siblings, though no sibling is named explicitly.

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?

Usage is only implied: 'public' plus 'Needs no connection' signals a browse-only tool requiring no auth, which is a useful condition. There is no explicit when-to-use statement or routing versus related siblings such as get_my_record or get_fan.

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