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

Annotations already cover read-only, idempotent, non-destructive, and closed-world behavior, so the description's job is to add business context — it does so by declaring the output is indicative (approximate) USD pricing and that no booking or lead side effect occurs. It stops short of saying whether out-of-area zips error out or how prices are banded.

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 short, front-loaded sentences with no filler; the price statement and the no-booking caveat both earn their place. The billing-cadence sentence is slightly cryptic out of context but still compact.

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?

With no output schema, the agent should know what an estimate looks like (single number, range, currency formatting) and whether modifiers change it materially; the description only says 'indicative USD price.' For a three-parameter pricing tool with zero schema documentation, more guidance was warranted.

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%, so the description carries full burden, yet it only glancingly alludes to serviceId semantics via 'Monthly billing differs from weekly visits.' The zip parameter and the five-value modifiers enum (spa, trees, large-pool, fountain) that clearly alter the estimate are given no meaning at all.

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: get an indicative USD price for one pool or spa. An agent can distinguish this from check_service_area (eligibility) and list_services (catalog), though it never names those siblings explicitly to reinforce the boundary.

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 clarifies the tool is advisory only ('No booking or lead is created'), which implies pre-booking usage, but never states when to prefer it over check_service_area, or whether area verification must happen first. Usage is inferable rather than explicit.

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