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

Annotations already declare readOnly/idempotent/non-destructive and closed-world, so the safety profile is covered. The description adds real behavioral context the annotations don't: the numbers come from published industry tables and public quotes rather than a mover's bid, and distance is resolved from stored route data "where it can" (hinting at a fallback). It stops short of describing behavior when no route is found or what currency/format guarantees apply.

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 sentences, each earning its place: what is returned, how distance may be supplied, and the nature/caveat of the data plus the usage trigger. The return shape and caveat are front-loaded before the usage 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?

No output schema exists, but the description explicitly characterizes the return value (low and high with currency). Combined with the 100% schema coverage and the annotation safety profile, an agent has everything needed to select and call this tool correctly.

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 coverage is 100%, so the baseline is 3, but the description adds the crucial relationship the schema does not express: distanceBand, miles, or from/to are alternative ways to supply distance, and the tool resolves distance itself when given places. That mutual-exclusivity/priority information is genuine added value beyond the per-field descriptions.

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 and resource ("Returns Haulest's research planning range... for a household move") plus scope (US, Canada, UK) and the inputs it derives the estimate from. It also implicitly separates itself from quote-obtaining siblings by calling the output a research range rather than a bid.

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?

"Use it when someone asks what a move might cost" gives a clear triggering context, and "not a bid from a mover" steers the agent away from treating it as a quote. However, it never names the alternative sibling (e.g. request_moving_quotes) that covers the actual-quote case, so the routing is implied rather than explicit.

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