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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false; the description reinforces this by stating the tool 'opens nothing by itself,' which explains the apparent contradiction with the name. It adds useful context that the return value is procedural guidance organized by screens, buttons, and fields, and that CoachingPortal has no public API. It does not cover auth/session prerequisites for the subsequent browser-based execution.

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?

Three compact sentences, front-loaded with the core behavior and the 'opens nothing' caveat. Minor waste in the trailing 'official API: CoachingPortal publishes no public API' phrasing, which is redundant on its face and only earns its place for the implication that a browser is required.

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 zero parameters, no output schema, and annotations covering the safety profile, the description supplies what an agent needs: what is returned, that nothing is executed, and which tool family completes the task. It is slightly thin on prerequisites, such as when the Cloud Browser session must already be authenticated to the user's account.

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 no parameters, so the schema carries no semantic burden and the baseline of 4 applies. The description correctly implies there is nothing to configure, though it could have stated explicitly that all leaderboard settings are supplied later during the in-app or browser flow.

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?

Despite a name that implies a write ('create_leaderboard'), the description explicitly reframes the tool: it 'returns how to do it in CoachingPortal step by step (screens, buttons, fields) and opens nothing by itself.' That is a specific, actionable statement of what the tool actually does. It falls short of a 5 because it never distinguishes this tool from the close sibling coachingportal_refresh_leaderboard or any of the other coachingportal_* entry points.

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?

The description gives a clear workflow: call this to get step-by-step instructions, then execute them with the cotlet_browser_* tools in the Cloud Browser. It implicitly tells the agent this tool alone will not accomplish the creation. It lacks explicit when-not guidance, such as what to do if the user already has a leaderboard or prefers a different path.

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