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

Annotations already declare read-only, idempotent, and non-destructive behavior. The description adds a valuable behavioral detail: 'Домены намеренно анонимизированы до покупки' (domains are intentionally anonymized until purchase), which is beyond the annotations and sets user expectations. No contradictions.

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?

Two concise sentences, front-loaded with the main purpose and a key caveat. Every word earns its place with no redundancy.

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?

The description covers the core output (platforms, metrics, languages, topics, price, free slots) and the important anonymization note. With zero parameters and a simple list-type operation, this is complete enough, though it omits pagination/ordering details which are likely handled by the output schema.

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 has zero parameters, and the empty schema provides full coverage. The description adds context about the returned content, which is sufficient given the absence of parameters.

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 states a specific verb ('Возвращает') and resource ('доступные международные iGaming-площадки') with detailed attributes (metrics, languages, topics, price, free slots). This clearly distinguishes it from sibling tools like list_links and list_tariffs.

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 description clearly implies this is the tool for iGaming donor data, with no exclusions or explicit alternatives. It provides clear context but does not explicitly contrast with sibling tools or state when-not-to-use.

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