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

Goes well beyond the annotations by disclosing the irreversible confirmation email ('cannot be unsent') and the deferred-booking flow ('nothing is booked until they confirm'). This is exactly the side-effect context an agent needs before triggering a non-idempotent, destructive write.

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 tight sentences, front-loaded with the action and immediately followed by the most consequential behavioral fact (the unsendable email). No filler.

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?

Behavior is well covered for a tool whose annotations already flag it as destructive and non-idempotent, and no output schema is needed. However, with 8 params at 0% schema coverage, the definition is incomplete on the input side.

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% across 8 parameters, so the description must carry the burden. It only faintly gestures at service, start, name and email while leaving lang, timeZone, notes, website and the 32-value service enum entirely unexplained.

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 ('Requests'), resource ('30-minute first call'), and scope ('about one service at an open start time'). It is clearly distinguishable from get_free_slots and list_services without opening any schema.

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?

'At an open start time' implies the caller needs slot data from get_free_slots, and 'one service' implies list_services, but neither is stated as an explicit prerequisite or alternative. No when-not guidance is given, so usage is only implied.

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