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

With no annotations, the description carries the burden alone; it does disclose the 90-day ceiling and, via 'PRO', an implicit paid-tier/access_token requirement. It omits units (C/F, mm/in), what happens for days beyond 90 or missing data, and the response shape, which matters for an unflagged read tool.

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 efficient sentence covering data content, granularity, and window, with the scope limit front-loaded. The opaque 'PRO.' prefix spends a leading position on a label the agent cannot decode.

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?

For a 3-parameter tool with no annotations and no output schema, the definition should say more about units, the default/behavior of `days`, and auth expectations. What is present is accurate but leaves an agent guessing on several call-shaping details.

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?

Schema coverage is only 33%, so the description must compensate. 'Up to 90 days' implies the upper bound for `days` and 'for a climate station id' ties to `station_id`, but the default for `days` and how to source a valid station id are not stated; only `access_token` is documented in the schema.

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?

States a concrete resource (daily max/min/mean temperature and precipitation) scoped to a climate station id with a 90-day window, which an agent can match to a historical-weather need. Siblings (compare_stations, nearest_station) are obviously different operations, so no disambiguation is needed, but the leading 'PRO.' token is unexplained and slightly muddies the opening.

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?

No explicit when-to-use or when-not-to-use guidance beyond the implicit 90-day cap. The description does not mention nearest_station as the way to obtain a station_id, nor compare_stations as the alternative for multi-station comparisons, leaving routing to inference.

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