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

Annotations already declare read-only, idempotent, non-destructive, open-world behavior, and the description adds genuinely non-obvious traits: the 7-day maximum window, newest-first ordering, the 24-hour default, and the NEA quirk that some readings are timestamped a few hours ahead ('the time is as published'). It does not cover behavior on empty results or invalid station codes.

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?

Front-loaded with what is returned and the time window, followed by the prerequisite and the timestamp caveat, so the most decision-relevant facts come first. The trailing 'Data from the NEA.' repeats the attribution already given in the first sentence and could be dropped.

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?

An output schema exists, annotations cover the safety profile, and the schema fully documents all six parameters, so the description only needs to supply window limits, defaults, the prerequisite call, and the timestamp anomaly — all of which it does. Nothing an agent needs in order to invoke 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?

Schema description coverage is 100%, so every parameter is already documented, including the 7-day from/to pairing, limit 1-100, pollutant enum list, and language codes. The description restates the 7-day cap and the 24-hour default but adds no new syntax, format, or interdependency detail beyond the schema, so the baseline 3 applies.

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?

Names a specific verb and resource ('Returns the hourly readings of one station'), pins the source (NEA Georgia), and states the scope (at most 7 days, newest first, with the level of each reading). An agent can distinguish it from air_get_quality, which the description explicitly frames as the lookup step rather than the history fetch.

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?

Gives an explicit prerequisite sequence: 'Call air_get_quality first to find the station code', plus the default behavior when no date range is supplied (last 24 hours). It stops short of stating when NOT to use it, e.g. what to do for periods longer than 7 days or for other stations' comparison.

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