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

Beyond the annotations, the description discloses important behaviors: retry safety via idempotency_key, that no funds are transferred, that payment credentials are not accepted, and that a deposit-required service may return a Kirah-hosted human payment continuation. These are meaningful, non-obvious side effects and boundaries not encoded in 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?

The description is three sentences with no filler. The primary action and user-confirmation requirement come first, followed by idempotency guidance and the payment caveat, which is an effective front-loaded structure.

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 and the presence of an output schema, the description covers the essential non-obvious context: exact-match booking, confirmation requirement, retry semantics, and payment behavior. It does not explain how to obtain service_id or provider_id from sibling tools, but the input schema and output schema cover most remaining structural detail.

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 low at 25%, and the description compensates only partially. It adds meaning to start_iso by requiring ISO-8601, and to idempotency_key by explaining safe retries, but it leaves tenant, client, agent_metadata, and intake_responses semantics to the schema and parameter names.

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 states a specific verb and resource: 'Creates one guest booking for an exact service, provider and ISO-8601 start time.' The explicit constraints and the user-confirmation gate make its purpose unmistakable and clearly distinct from siblings like cancel_booking and reschedule_booking.

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 invocation conditions: call only after explicit user confirmation, reuse idempotency_key for safe retries, and do not expect to pass payment credentials through MCP. It provides strong usage context but does not explicitly name alternatives or say when not to use this tool, so it stops short of full routing guidance.

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