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

Annotations already declare destructiveHint=true, readOnlyHint=false, and idempotentHint=false, so the safety profile is covered structurally. The description adds the confirm=true gate and the 'sensitive' framing, but does not say what state is overwritten, whether unspecified fields (e.g. day columns) are cleared, or what authorization is needed.

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 compact sentences, front-loaded with the action, no filler or restatement of the title. Every clause 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 write with 21 loosely documented parameters and no output schema, the description omits what a schedule payload actually contains and what the update affects. The confirmation gate is the only substantive context provided.

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?

With 21 parameters at only 29% schema description coverage, the description is expected to compensate and does not: it names only confirm (already documented with a const and a schema description). The day fields, users, frequency, custom_message, default_events and auth parameters are left unexplained.

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 gives a clear verb+resource ('Updates a schedule') and even the endpoint path. It does not, however, distinguish this from siblings like create_schedule, delete_schedule, get_schedule, or the assign/remove_users_from_schedule variants, so the agent must infer scope from the name alone.

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?

'Limitations: sensitive write operation; requires confirm=true' states a gate the caller must satisfy, which is real usage guidance. It stops short of saying when to choose this over assign_users_to_schedule or batch variants, and gives no when-not guidance.

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