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

Annotations already declare the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false, openWorldHint=true), so the bar is lower. The description contributes the useful fact that this is a partial mutation across a listed field set, but omits an important consequence: setting isDefault presumably unsets the previous default schedule, and changing availability changes live booking availability.

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?

A single front-loaded sentence listing exactly the mutable surface, with no filler or repetition of the title. Every clause earns its place.

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 6-parameter mutation with nested objects, no output schema, and only 50% schema description coverage, the description is minimally adequate. It doesn't cover partial-update semantics (are omitted fields preserved?), the default-schedule side effect, or what a successful response confirms.

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 50%, so the schema carries much of the burden (it documents scheduleId and describes 'overrides' and 'availability' semantics). The description enumerates five of the six parameters in plain language but adds no meaning beyond the field names — notably it doesn't clarify how 'weekly hours' maps to the `availability` structure vs `overrides`.

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?

Specific verb ('Change') plus resource ('a schedule') and an explicit enumeration of the mutable fields (name, time zone, weekly hours, date overrides, default). That clearly separates it from create_schedule/delete_schedule/get_schedule, though no sibling is named.

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?

No when-to-use, when-not-to-use, or prerequisite guidance. It never says the schedule must already exist, that scheduleId comes from list_schedules (only implied via schema), or when to prefer this over create_schedule, duplicate_schedule, or bulk_set_default_availability.

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