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

Annotations already declare readOnlyHint/openWorldHint/destructiveHint=false, so safety is covered; the description adds real non-obvious behavior by disclosing that omitting 'page' starts at the user's own page and that results can be broken down per language, country and board type. It stops short of documenting pagination termination or result size.

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 front-loads what the tool returns, then adds the paging caveat and the endpoint. Nothing is wasted, though the semicolon-chained clauses and parenthetical require a second read.

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 output schema, the description carries the return-shape burden and does so by listing rank, member and coding time by dimension. Combined with the paging note and endpoint, an agent has enough to call it correctly; only pagination limits remain unstated.

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 every parameter including the board_type enum is already documented in the schema; baseline 3 applies. The description adds only a light mapping of the grouping dimensions (language, country, board type) to the output, which the schema largely already conveys.

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 verb+resource ('The ranking of a private leaderboard') and enumerates the returned fields (rank, member, total coding time). The word 'private' plus the endpoint path GET /users/current/leaderboards/{board} distinguishes it from sibling wakatime_get_public_leaders without opening either schema.

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 implied rather than stated: it notes paging behavior and the board_id description points to wakatime_list_private_leaderboards as the source. However, it never says when to choose this over the public-leaders sibling or the leaderboard-listing tool, and no exclusions are given.

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