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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuinely useful behavior beyond that: the paid-package requirement and the cost of 2 request units per call, which an agent cannot infer from structured fields.

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, front-loaded fragments with no filler: purpose, endpoint, cost. Slightly telegraphic, but every element 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?

For a simple two-parameter read tool with no output schema, the description covers purpose, endpoint, cost, and prerequisites. The only gap is the undocumented 'ilce' parameter, which is minor.

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 50%: 'il' is documented in the schema, 'ilce' is not. The description only restates that ilce is optional, which the required list already implies, and adds no format or semantics for the undocumented district parameter.

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 the resource (nöbetçi eczaneler) and its scope (il, isteğe bağlı ilçe), so an agent knows exactly what it returns. It does not need sibling differentiation since no sibling covers pharmacies, but it also does not explicitly say so.

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 prerequisite 'Ücretli paket gerekir' tells the agent a paid plan is needed, which is real usage context. However, there is no guidance on when to prefer this over alternatives or what happens if the district is omitted.

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