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

With no annotations, the description carries the full burden and does disclose the key return behavior: buyUrl plus trackingTag, with affiliateUrl as a compatibility alias. It does not explain side effects, permissions, rate limits, precedence among asin/url/keywords, or failure behavior, so important behavioral context is still missing.

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 definition is a single front-loaded sentence with no wasted language. It efficiently states the resolution target, accepted inputs, marketplace scope, and primary output fields.

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 7-parameter tool with no annotations and no output schema, the description is adequate but incomplete. It names the main output fields and input alternatives, but does not cover several parameters or behavioral details needed to invoke it confidently in all cases.

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?

The description adds meaning for three otherwise bare inputs (asin, url, keywords) and references the selected marketplace, but schema description coverage is only 29%. It does not explain ageBand, category, the required locale semantics beyond what the schema already says, or how multiple input forms interact.

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 gives a specific verb and resource: it resolves ASIN, Amazon URL, or keywords into a curated buy URL on a selected marketplace. It is clearly not a registry or general catalog-search operation, but it does not explicitly distinguish itself from siblings such as search_catalog or search_suggest.

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?

The accepted input forms imply that the tool is used when an agent already has an ASIN/URL or keywords and needs a buy URL. However, there is no explicit guidance on when to use this instead of search_catalog or search_suggest, and no exclusions or prerequisites are stated.

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