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

Annotations already indicate destructive and idempotent behavior; the description adds valuable context about side effects (creating customer/job records, sending notifications) and idempotency (replaying is safe and returns stored result). It doesn't detail error cases or authentication requirements, but with annotations covering the safety profile, this is a strong addition.

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?

The description is well-structured, front-loading the primary precondition and followed by side effects and outcome interpretations. Every sentence adds essential information without redundancy.

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 the tool's complexity (side effects, idempotency, status interpretation), the description covers key aspects. An output schema exists, so return values needn't be described. However, it doesn't mention what happens on invalid codes or missing booking, which could be useful for error handling. Mostly complete.

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 0%, so the description must compensate. It explains that the 'code' is a six-digit SMS code from request_booking and implies 'booking_id' identifies the booking. However, it doesn't clarify the format of booking_id (UUID is in schema) or any other parameter details. Baseline 3 is appropriate given the schema has some structure but no descriptions.

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 clearly states the tool's purpose: confirming a booking using a six-digit SMS code obtained after request_booking. It explicitly differentiates from sibling request_booking, and the title reinforces the specific action.

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?

Provides explicit timing: 'Use this after the customer supplies the six-digit SMS code from request_booking.' It also gives clear interpretation rules for status codes and booked flag, distinguishing confirmed appointments from callback_pending follow-ups. No alternative tools are suggested, but the context is precise.

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