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

Annotations only declare readOnlyHint and openWorldHint; the description adds genuinely new behavior: no invented Associates tags, server-configured per-storefront tags, amazon.se default, and that non-curated marketplaces degrade to romantic search deep-links rather than /dp. That fallback disclosure is exactly the kind of context annotations cannot carry. It omits error/failure behavior, keeping 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?

Three dense sentences that front-load what the tool returns before the usage constraint. The trailing "OpenAPI: resolveProduct" is an operationId restatement that adds no decision value.

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 an 8-parameter tool with no output schema, the description covers the two required params and the output shape well, but leaves three enum filters unexplained despite their likely influence on the generated search link. Adequate, not complete.

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 63%, and the description adds real meaning for marketplace (domain vs id, per-storefront catalog behavior) and locale. But occasion, styleTag, and budgetBand are never explained in either schema or description, so their effect on resolution is left to inference.

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 precise verb (Resolve) and enumerates its accepted inputs (ASIN, pasted /dp/ URL, keywords) plus the produced artifact (buyUrl). That output framing distinguishes it cleanly from siblings like search_gifts and get_catalog, which the description implicitly routes around.

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?

"ALWAYS pass marketplace + locale for the user" gives a hard usage constraint, and the input enumeration implies when to pick this tool (you have an ASIN/URL/keywords). It never explicitly contrasts with search_gifts or says when not to use it, so it falls short of full routing guidance.

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