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

Annotations declare readOnlyHint=true and openWorldHint=false, and the description is consistent with both. It adds genuinely useful context beyond the annotations: the rolling 7-day window, that results are aggregate counts only, and that no key is required. It does not describe result size or ordering, which keeps it from a 5.

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-loaded with the returned content and scope, with no filler. It is long but every clause (time window, metrics, aggregate-only, no key) carries information.

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 parameters, no output schema and light annotations, the description fully carries the burden and does so: it explains what is returned, the time window, the metric types, and the aggregation/auth posture. Nothing needed to call it correctly 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 nothing for the description to disambiguate; baseline 4 applies. 'additionalProperties: false' on an empty object confirms no hidden 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 precisely: rising hashtags with post counts and most-shared products, platforms and brands with share counts over a rolling 7-day window. This clearly sets it apart from the influencer lookup/search/compare siblings, which none of them touch trend aggregates. It lacks an explicit action verb ('get'/'fetch'), but the returned content is 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?

The 7-day window implies when the data is applicable, but there is no explicit 'use this when' statement or mention of alternatives. Usage is inferable from the scope rather than stated.

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