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

Goes well beyond the annotations by disclosing a critical negative behavior: it does NOT block or reserve the day, and only a created booking blocks a day. It also describes the return payload (available=true/false with alternative dates, held=false). This adds real side-effect clarity that readOnlyHint/idempotentHint alone would not convey.

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 short sentences, each load-bearing: what it does, the side-effect caveat, the return shape, and the call-order guidance. The most decision-critical fact (it does not hold the day) is front-loaded in sentence two.

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 annotations covering the safety profile and an output schema present, the description still contributes the booking-model caveat and the sequencing with create_booking. An agent has everything needed to call this correctly in the booking flow.

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?

Three required params with schema coverage at 67%: pickup_date and pickup_time carry format/timezone descriptions, but quote_id is undocumented in both the schema and the description. The description adds no parameter-level meaning, so the baseline of 3 for largely schema-documented params applies.

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 ("Re-checks that the quoted date is still free") with clear temporal scope ("right before the booking"), which differentiates it from the sibling check_availability. It does not name that sibling explicitly, so the agent must infer the distinction from timing rather than an explicit callout.

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?

Gives an explicit trigger ("when the customer wants to proceed") and the follow-on flow ("show the summary and create the booking right after their explicit yes"), which routes the agent through the booking sequence. It stops short of naming when to use check_availability instead, but the usage context is unambiguous.

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