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

Annotations already declare destructiveHint=true and idempotentHint=false, and the description goes beyond them by flagging the operation as 'sensitive', naming the required permission (manage users) and the mandatory confirm=true guard. It stops short of saying whether locks can be released (no unlock sibling exists) or what happens to pre-existing locked entries, so it is strong but not complete.

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?

Three compact sentences: action and scope first, payload format second, caveats third. No filler or repetition, though the 'Limitations:' label bundles unrelated facts (sensitivity, permission, confirm) into one clause.

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 and a destructive, non-idempotent operation, the description covers the confirmation and authorization burden but omits what locking actually does (presumably freezes time events from edits) and how to recover from a mistake. For a destructive admin tool this leaves a meaningful gap, though the annotations and schema carry part of the load.

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 67%: the description restates the data entry shape (user_id + lock_date) and the YYYY-MM-DD format that the schema pattern already enforces, and confirms that confirm must be true. It never mentions the optional account_id parameter, which is the one field whose semantics (required for multi-workspace users) an agent might miss.

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 ('Locks time events') plus scope ('for one or more users from the specified dates'), which is far more precise than the title alone. No sibling is named, but the lock concept is unique enough among the siblings (archive/update/delete_event, approve_timeoff) that an agent can distinguish it without help.

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?

Prerequisites are stated ('requires permission to manage users and confirm=true'), which implies the tool is a deliberate administrative action rather than a routine call. However, there is no guidance on when to prefer this over update_event / update_events_batch, no when-not condition, and no note on the effect of locking already-locked dates.

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