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

The annotations already declare readOnlyHint, idempotentHint, and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds one genuinely new behavioral fact — it reports *stored* coverage, i.e. what has already been collected rather than a live query — but gives no indication of return shape or whether results are cached/stale, which matters because no output schema exists.

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?

Two short sentences with the action directive ("Start here") front-loaded, so the agent's first read yields the routing decision. The second sentence is dense with undefined jargon, but nothing is padding or repetition of the title.

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?

Complexity is low (zero parameters, read-only), which lowers the bar, but there is no output schema and the description never says what a "coverage" response contains or how an agent should act on it. For a self-declared entry-point tool, the omission of return content leaves the most important question open.

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 nothing for the description to disambiguate. The baseline of 4 applies; no parameter guidance is needed or missing.

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?

"Measured stored coverage and collector context" names a resource (coverage) and implies it reports what data has been collected, which distinguishes it from fetch/stats/odds siblings. However, "coverage" and "collector context" are jargon that never resolves into a concrete object — coverage of what (games, players, slates, sportsbooks?), and what form the measurement takes. An agent knows it is a status/orientation tool but not precisely what it reports.

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?

"Start here" is an explicit, front-loaded call-order directive, which is exactly the guidance an orientation tool needs against 16 siblings. It stops short of stating what to do next or when it can be skipped, so it is clear context without exclusions.

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