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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds meaningful behavior beyond that: it reports enabled:false when booking is off or not in the plan, excludes the current slot when a bookingId is passed, warns that invalid start times are rejected, and discloses server-side range clamping. No contradiction with annotations.

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?

Four dense sentences, each earning its place: purpose and computation, special return value, rescheduling workflow and rejection behavior, and range clamping. The main purpose is front-loaded and there is no filler or repetition of schema content.

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?

Given that an output schema exists and read-only annotations already cover safety, the description covers all necessary invocation context: availability computation, enabled:false handling, bookingId semantics, the precondition for reschedule_booking, and server-side range limits. Nothing essential for a correct call is missing.

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%, so the schema documents all three parameters. The description reinforces bookingId's role by explaining the current slot is 'not counted as taken', but it adds little beyond the schema's own description for that parameter and nothing new for fromDate/toDate. This meets the baseline without exceeding it.

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 opens with a specific verb and resource: 'Read the current team's bookable time slots in a date range'. It further distinguishes the tool from siblings like list_bookings by explaining slots are 'computed from the team's weekly booking rules minus what is already taken', making the availability concept unmistakable.

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 description gives explicit guidance: pass bookingId for rescheduling and 'always call this before reschedule_booking' because an out-of-range start time is rejected. It does not explicitly state when to prefer list_bookings or other sibling tools, but the availability-versus-bookings distinction is sufficiently clear for routing.

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