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

Annotations already show readOnlyHint=false, but the description adds crucial side-effect details: the request appears on Foundaree and via email, the person calls back if available, and nothing is confirmed until the call happens. It also discloses a rate limit ('One open request per phone number and person; a few per number a day'), which is not 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 moderately long but every sentence carries essential information: purpose, examples, safety, consent, side effects, rate limit. It is well-structured and front-loaded with the action and examples, 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?

For a mutating tool with real-world side effects, the description covers the full workflow: lookup prerequisite, user consent, what happens after the request (person sees/calls back), and confirmation semantics. Since an output schema exists, return values are not needed, and the description leaves no critical gap.

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?

The input schema provides 100% parameter descriptions, so the baseline is 3. The description adds useful constraint on 'name' and 'phone' by emphasizing they must be the user's own and never guessed/reused, and it tells how to source 'username' (search_people/match_people), but these are also partially in the schema.

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 action: 'Send a booking request to one person on Foundaree' and provides concrete examples ('book this plumber', 'ask this dentist'). It distinguishes itself from sibling search tools by instructing to use search_people or match_people first, positioning this as the action after discovery.

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 an explicit trigger condition: 'Use it only when the user asked to book or contact that person' and requires prior lookup ('Find the username with search_people or match_people first'). It also mandates user consent before the call and forbids guessing phone numbers, which is clear when-to-use guidance.

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