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

Annotations already declare that this is a non-read-only, open-world, non-destructive, non-idempotent write. The description adds real context beyond that: it is free to the homeowner, a vetted pro calls back within the hour during business hours, and the response includes a reference and next steps. The gap is that it never warns that resubmitting creates a duplicate request, which matters because idempotentHint=false.

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 lead sentence is front-loaded and effective, but the callback information is stated twice in near-identical form ('A vetted local pro calls them back (a vetted local pro calls back within the hour...)'), which is wasted space. The trailing ZIP instruction would read better placed earlier, before the return-value note.

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 seven-parameter write tool with no output schema, the description covers cost, callback timing, consent requirements, and the shape of the response ('a reference and what happens next'), which is the important information. It falls short only on failure behavior and duplicate-submission consequences for an explicitly non-idempotent operation.

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 100%, so every one of the seven parameters is already documented, which sets the baseline at 3. The description adds only marginal meaning, such as tying the ZIP to the service-area check and emphasizing that the contact person is real and consenting, but says nothing extra about 'need', 'language', or 'preferred_time' beyond 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 names a specific verb and resource ('Book snow plowing') plus a geographic scope (North Jersey) and the audience constraint ('a real person who asked for it, with their consent'). It also implicitly separates itself from check_service_area by assigning ZIP validation to that sibling, so an agent can distinguish the two without opening schemas.

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 precondition (consent from the person) and names the alternative with the condition that selects it: 'Check the ZIP with check_service_area first if unsure.' What's missing is a clear when-not-to-use case, such as out-of-area ZIPs or already-booked requests, but the routing guidance is concrete.

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