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

Discloses rich behavior beyond annotations: the previous document moves to version history, recovery is possible via the cabinet UI, and a stale updated_at triggers a 409 refusal rather than silent overwrite. This is exactly the kind of context annotations (destructiveHint=true) 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?

Front-loads the action, then the version-history behavior, then the mandatory concurrency rule. Efficient with some line wrapping; every sentence 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 destructive mutation with no output schema and 0% schema docs, the description covers the critical risk (overwrite prevention via updated_at, recoverability via version history). Minor gap: the shape/format of the document object is unspecified.

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 0%, so the description must compensate. It explains updated_at as an optimistic-concurrency token sourced from get_lesson and ties title/document to the update, though it doesn't clarify that both are optional/nullable or what document's shape is.

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: changes the title and/or document of a lesson. Clear enough to distinguish from create_lesson and get_lesson, though it doesn't explicitly name those siblings.

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?

Explicitly prescribes the required workflow: 'Сначала get_lesson, потом правка' and mandates passing updated_at from get_lesson when replacing the document. Names the alternative (get_lesson) and the ordering constraint.

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