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

Beyond the annotations it discloses an auth requirement ("Needs a PostThisDeal agent key"), a rate/caching behavior ("repeated requests for the same offer within minutes return the last result"), and precise failure semantics ("A failed or unreadable check verifies nothing"). It also enumerates the possible request_status outcomes, which the openWorldHint/non-idempotent annotations alone would not reveal.

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 action and its scope are front-loaded, and every sentence carries real information about limits or outcomes. It is fairly dense across five sentences, and the explanation of request_status/verification_established partly overlaps the output schema, which keeps it just below maximum efficiency.

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 one-parameter tool that triggers an external, non-destructive but non-idempotent check, the description covers the auth need, caching behavior, failure interpretation, and the exact limits of what a confirmation means. Because an output schema exists, return values need not be restated, so nothing an agent needs is missing.

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% and the single offer_id parameter is already documented as coming from search_deals, so the schema carries the parameter burden. The description adds no further detail such as format, range, or what happens with an unknown id, so the baseline of 3 applies.

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 opens with a specific verb and resource: "Request a fresh check of the offer at the retailer, and report exactly what could and could not be confirmed." The word "fresh" and the caching note distinguish it from the read-style siblings like get_offer or get_price_context, so an agent can tell what this tool uniquely does.

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 a clear condition for use (a fresh check is wanted) and a strong scope boundary: "A page check confirms a listed price and availability at most — never that a coupon code works," which implicitly routes coupon questions to check_eligibility. It stops short of explicitly naming that sibling as the alternative, so it is clear context rather than a full when/when-not map.

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