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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds real behavioral value beyond that: the exact throttle values, the per-minute unit of measure, and the literal endpoint GET /api/v2/{username}/throttle. It does not describe the response shape or any auth requirements, which keeps it below 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?

Three short sentences, front-loaded with what is returned, followed by the actionable guidance and the endpoint. Every sentence carries information; nothing is redundant with 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?

With no parameters, no output schema and safety already covered by annotations, the description supplies what an agent needs: the meaning of the values, the unit, the tier thresholds, and when to consult it. Only the exact response structure is left implicit, a minor gap given the reading returns two related values.

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 and the baseline is 4. The description correctly implies the username is resolved from the endpoint path rather than supplied as an argument.

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 (the account's data rate limit and current active rate) with concrete semantics — data-record modifications per minute, quantified as 30 on free and 60 on Plus. An agent can distinguish this diagnostic from publishing siblings like adafruitio_publish_data_point without opening any schema.

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?

It gives explicit usage context: 'Check it before publishing many points,' which ties the tool to a concrete decision point involving a named sibling workflow. It stops short of stating when-not to call it (e.g. that it is unnecessary for single-point writes), 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.