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

With no annotations provided, the description carries the full burden. It discloses key behaviors: only a 15-minute hold, no charge, no payment information accepted, and idempotency for retries. It does not mention return format or error handling, but the disclosed behaviors are important and well-stated.

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 a single, well-structured paragraph that front-loads the purpose and key constraints. Each sentence adds value; there is no fluff. It could be slightly more compact, but it is efficient and readable.

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 an 11-parameter tool with no output schema, the description covers the main behavioral aspects but omits what the response contains (e.g., reservation ID) and error conditions. It also does not describe the other required parameters. It is adequate for a basic call but not fully 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 coverage is only 45%, so the description must compensate. It adds meaning to start_time (ISO 8601, at least 6 hours in future) and idempotency_key (stable for retries). However, it does not explain the other required parameters like shoot_type_id, package_id, city_id, or address coordinates, which remain underspecified.

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 verb 'Book' and the resource: a specific photographer, package, date/time, and address on the user's behalf. It also distinguishes itself from siblings by explicitly mentioning the follow-up get_payment_link, which is a different operation. The purpose is 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?

It gives explicit usage guidance: 'Immediately follow this with get_payment_link' and instructs the agent to give that URL to the human. It also specifies when to use idempotency_key for retries and states that no login is required. This is strong, actionable guidance.

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