dictionaries.get

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds that it's a read operation ('чтение') and lists the types of data returned, which is useful context. However, it doesn't disclose behavior like pagination, response size, or that DictionaryNames accepts a limited set of values (though the schema mentions 15 values). No contradiction with annotations.

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?

The description is concise: two sentences plus a documentation link. The first sentence front-loads the purpose with a clear list of examples. The second sentence identifies the service/method and provides a link. No wasted words, though the list is somewhat long.

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 read-only tool with one parameter and full schema coverage, the description is mostly adequate. It explains what data is returned and provides a documentation link. However, it doesn't mention that DictionaryNames values are limited to a specific set (the schema says 'полный список: direct_fields' but doesn't link it), and there's no output schema, so the return structure is not described. The description could be more complete by enumerating valid dictionary names or pointing to the direct_fields tool.

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 the schema already documents the single parameter DictionaryNames. The description adds context by listing example dictionary names (Currencies, MetroStations, GeoRegions, GeoRegionNames) and mentions '15 значений', but it doesn't fully enumerate the valid values or explain the format. The description adds some value but the schema carries the main burden.

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 clearly states the tool's purpose: it returns reference data (dictionaries) from the Yandex Direct API, listing concrete examples like regions, time zones, currencies, metro stations, parameter restrictions, external networks (SSP), and Crypta segments. It identifies the service and method (dictionaries, get) and provides a documentation link. It doesn't explicitly differentiate from siblings, but the resource (dictionaries) is distinct from the other get_* tools.

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 implies usage: it's a read-only method for retrieving reference data. It doesn't explicitly state when to use this tool versus alternatives, but the resource name 'dictionaries' and the list of data types make it clear it's for reference data, not for ads, campaigns, or reports. The documentation link provides additional context, but no explicit when/when-not guidance is given.

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