Список кампаний

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

Annotations already cover the safety profile (readOnlyHint, openWorldHint), so the description goes beyond by disclosing a non-obvious behavioral boundary: MCBANNER campaigns are absent by API design, not by filter or auth failure — an important trap for an agent. It also discloses currency units and the default projection, though it says nothing about rate limits or result caps beyond the schema.

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?

Four sentences, front-loaded with purpose then progressively adding field behavior and the API-boundary caveat. Each sentence carries information, though the default-field enumeration slightly overlaps the schema text.

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 stating what is returned by default, how to widen the projection, and which campaigns will never appear. For a 5-parameter, read-only list tool this covers everything an agent needs to invoke it 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 the baseline is 3, but the description adds real meaning: budgets are denominated in rubles (relevant to DailyBudget/Funds), the default returned field set, and the purpose of 'fields'. The default-field list is partly duplicated from the schema, keeping it from a 5.

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?

States a specific verb and resource ("Список рекламных кампаний Яндекс.Директ") plus the supported filter dimensions (status and type). The plural 'список' clearly separates it from the singular get_campaign sibling without needing further contrast.

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?

Explains how to operate the tool: default field set applies, and other CampaignFieldEnum fields must be requested explicitly via 'fields'. It also sets expectations that MCBANNER campaigns are never returned. It lacks explicit when-to-use-vs-alternative routing (e.g. vs get_campaign or manage_campaigns), so it stops short of a 5.

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