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

Beyond the readOnly/openWorld annotations it adds meaningful behavior: results come from the public fishersci.com search via a residential proxy, prices are the logged-out list price, results are capped at 15 families per page across pages 1-10. It also discloses the x402 billing model ($0.002 USDC per successful call; failures free), which the annotations do not cover. Only the absence of failure modes or throttling detail keeps it below a 5.

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?

Two sentences, front-loaded with the scope and return fields, followed by provenance and payment terms. The field enumeration is dense but every clause carries information. Minor tightening is possible in the price/payment sentence.

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?

An output schema exists, so the field list in the description is a bonus rather than a gap-filler, and the pagination ceiling plus billing terms cover what an agent needs to call it correctly. What remains thin is failure behavior (empty results, out-of-range pages) and any guidance on choosing this source over comparable lab-supply siblings.

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 both q and page are already documented, and the description adds only the page-1-to-10 ceiling and 15-results-per-page sizing. That reinforcement is mildly useful but does not explain query syntax or what happens on an out-of-range page. Baseline 3 fits when the schema carries the load.

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 (Fisher Scientific US lab product search) and enumerates what is returned: product family title, description, leaf category, starting list price, catalog numbers, specs and link. That clearly separates it from sibling lab-supply tools such as ecommerce_avantor_vwr_international or social_labx_com.

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?

Usage is only implied through the field list and the parenthetical caveat that account-specific pricing is not included. The description never says when to pick this over a rival lab-supply source, nor when to stop paging or use a different query style. Adequate context, but no explicit routing or exclusions.

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