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

Annotations already declare readOnly/idempotent/non-destructive/openWorld, so the safety profile is covered; the description adds genuinely new behavior — endpoint path, availability on all plans including free, a 2 request-unit cost per call, and Turkish-language JSON with `source` and `guncelleme` fields. This is exactly the cost/auth/return-language context annotations cannot express, though it omits failure behavior (e.g. what happens when a location resolves to nothing).

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, followed by the location-selection rules and then operational metadata (endpoint, plan, cost, response language). Every sentence carries information, though the location examples are slightly verbose and could be tightened without loss.

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 output schema, the description compensates by naming the response language and key fields (`source`, `guncelleme`). Together with location-resolution rules, pricing, and plan availability, an agent has everything needed to call this six-parameter, zero-required-parameter tool correctly.

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 100%, so baseline would be 3; the description earns more by adding what the schema does not — the mutual exclusivity rule between the location parameter groups and the Turkish-character normalization note ('Düzce' = 'duzce'), which prevents malformed lookups. It does not explain the `saat` forecast horizon, but that parameter is already well 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?

The first clause names a specific verb and resource — 'Returns current and hourly forecast air quality' — and enumerates the measured pollutants (PM2.5, PM10, NO2, O3, SO2, CO, dust, UV) plus AQI scales. That is enough to separate it from the weather siblings (hava, hava_detay) 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 clearly states the three mutually exclusive ways to specify a location ('give one') and shows the fallback ladder: `il`(+`ilce`) → `konum` slug → `enlem`+`boylam` for nearest district. It does not explicitly say when to prefer this over the weather tools or that konumlar_* tools should be called first to obtain a slug, so the routing guidance to siblings is only implied.

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