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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so safety is covered structurally. The description itself adds real behavioral context beyond that: the board is scoped to the current period and ranking is "by verified revenue added, never by votes" — a non-obvious ordering rule an agent would otherwise guess wrong.

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 subject and time scoping front-loaded, followed by the returned fields and the ranking rule. Every clause carries information; the only mild density cost is the inline field list, which is still readable and useful given no output schema exists.

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 must carry the return shape, and it does by naming name, tagline, category, verification tier, live rank and page. Minor gaps remain: no indication of result volume, page size, or whether an empty board is possible for a period.

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 meaning to add and the baseline of 4 applies. The description correctly spends no words on input arguments and instead describes the returned shape.

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 and scope ("the current launch period's board on Apptiller Launches") and enumerates the fields each entry carries, so an agent can tell this is a read of the live leaderboard rather than a submission or account action. It lacks an explicit verb ("browse"/"returns") and never names a sibling, but the domain and output shape are unambiguous.

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: the phrase "current launch period" signals this cannot be used for historical or arbitrary-period data, which is a useful boundary. However, there is no explicit statement of when to prefer this over the other sibling tools, no prerequisites, and no stated exclusions beyond the period scoping.

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