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

readOnlyHint=true already establishes the safety profile, so the bar is lower. The description adds genuine context beyond the annotations: a fixed cardinality of 10 and the fact that both a human page URL and a JSON API endpoint are returned, which helps an agent know it can chain into the API. It stops short of noting ordering or pagination (likely moot at a fixed 10).

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 front-loaded sentence with zero filler. The cardinality and the URL/endpoint payload are the two facts an agent actually needs, and both appear immediately.

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 present, the description needn't detail return structure, and it correctly adds only the high-level shape (10 boards, page URL, API endpoint). For a zero-parameter read-only list tool this is essentially complete; only an explicit 'use this first to discover board ids' pointer is missing.

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 no parameter semantics to document and the baseline of 4 applies. Nothing in the description misleads about inputs.

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 states the resource and scope precisely — 'The 10 leaderboards on GitHub Hot Board' — which clearly distinguishes it from the singular sibling get_board. However, it describes the return payload rather than naming the listing action with an explicit verb, leaving the 'list' semantics to be inferred from the tool name.

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: enumerating the boards and their endpoints suggests this is the discovery entry point before calling get_board or get_board_movers, but the description never says so explicitly and names no alternatives or conditions.

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