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

Annotations already indicate read-only and non-destructive behavior, and the description goes further: 'Nothing is held' explicitly states no side effects. It also discloses selection behavior (closest ten else balanced spread plus earliest open time) and the empty-result reason, which are meaningful behavioral details beyond the 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?

Three dense sentences with no filler. The core action and date constraint are front-loaded, followed by return behavior and the workflow hook to hold_xona_booking_slot. Every sentence 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?

The description is complete for a read-only listing tool: it covers date constraints, selection algorithm, empty behavior, output identifiers, and the no-hold guarantee. With annotations and an output schema present, there is no critical missing context for an agent to select and invoke the tool correctly.

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%, so the description is expected to add meaning. It adds inclusive date-range semantics, the 8-week maximum, the preferred_time ranking behavior, and maps 'one service' to service_id and 'connected practice' to practice_slug. It does not elaborate on doctor_id beyond the schema's existing explanation.

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: 'List open times at a connected practice for one service between date_from and date_to'. It clearly distinguishes this from public slot listing and from holding a slot, making the tool's purpose unambiguous.

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 clear context by saying each slot has a slot_fingerprint and date for hold_xona_booking_slot, signaling this tool is the read-only precursor to holding. It does not explicitly say when to prefer this over list_public_booking_slots, but the 'connected practice' framing implies the intended internal booking workflow.

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