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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds real context beyond that: results are capped at 5 offers per product with orderable ones first, and offers indicate JENNi orderability. It doesn't mention rate limits or failure modes, but it discloses the important result-shaping behavior.

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?

Front-loads what is searched and where, then packages the return shape, the offer cap, and the checkout handoff. Dense but every sentence carries operational information; the checkout-flow sentence is slightly tangential to invocation.

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 an output schema present, return values need not be enumerated, yet the description still explains the offer ordering, the 5-offer cap, and the guest-checkout path via url. Combined with the get_product pointer, an agent has everything needed to call and act on results.

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 all five parameters are already documented in the schema. The description reinforces the ZIP format and the store_id/zip pairing, but adds little beyond the schema baseline, which warrants the standard 3.

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 (search products) plus its scope: US ZIP codes or named markets. It also names the sibling it complements, get_product, for retrieving all offers, so an agent can separate 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?

Explains the two entry modes (ZIP for local delivery plus nationwide fallback, or a market key) and points at get_product when all offers are needed. It does not state when to prefer find_stores or when a ZIP is unsuitable, so it stops short of explicit exclusions.

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