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

Annotations already declare this as a read-only, idempotent, non-destructive, closed-world operation, so the safety profile is covered. The description adds real context beyond that: the S3 figure is obtained by traversing the bucket (implying a potentially costly/latency-heavy call) and the Yandex.Disk variant also surfaces the account's remaining space. That is useful behavioral disclosure the annotations cannot convey.

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 sentences, front-loaded with what is returned, then the per-backend computation caveats. Every clause carries information and nothing is padded; it could be marginally tighter but there is no waste.

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?

There is no output schema, so the description must convey the return shape, and it does: platform disk usage, own-storage usage, and (for Yandex.Disk) account remaining space, plus how the S3 number is derived. Adequate for a single-parameter read tool, though it stays silent on formatting/units.

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% and the single workspace_id parameter is already documented in the schema ('ID воркспейса (из workspace://list)'). The description adds nothing about the parameter, so the baseline of 3 applies — the schema does all the work.

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 ('Возвращает занятое файлами место') and breaks the result into two clearly named components: the platform disk that counts toward the tariff quota and the user's own storage. That is concrete enough for an agent to know what comes back, but it never distinguishes itself from the nearby sibling get_workspace_storage, so it stops short of a 5.

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 purpose implies when to call it (checking storage consumption), and the S3/Yandex.Disk clauses hint at backend-specific behavior, but there is no explicit when-to-use or when-not-to-use guidance and no mention of the get_workspace_storage / get_workspace_tariff alternatives an agent would otherwise have to disambiguate from. Usage is only implied.

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