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

Goes meaningfully beyond readOnlyHint/openWorldHint by disclosing two non-obvious behaviors: links omit ?tag= until Associates IDs exist, and curated ASINs only yield /dp on amazon.se while other marketplaces degrade to search deep-links. That degradation rule is exactly the kind of surprise an agent needs warned about. It does not cover failure behavior for an invalid or non-Amazon ASIN.

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 short sentences, front-loaded with the resource and accepted inputs, then the caveats. The ?tag= omission note is duplicated verbatim-ish in the marketplace parameter description, which is minor waste but not harmful.

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?

Covers the core resolution path and the marketplace degradation rule, which is the main risk area for a seven-parameter open-world tool with no output schema. However, occasion and styleTag are left wholly unexplained, and there is no guidance on what comes back or what happens when the ASIN is invalid or unavailable in the requested marketplace.

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?

At 71% schema coverage the baseline is 3, and the description mostly reinforces what the schema already says (marketplace/locale required, ASIN-vs-keywords). The two enum parameters, occasion and styleTag, have no description in either the schema or the prose, so their effect on the resulting URL is undefined. Real added meaning beyond the schema is limited to the marketplace/tag caveat.

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?

Names a specific verb (resolve) plus the accepted inputs (ASIN, pasted /dp/ URL, keywords) and the output form (product /dp or dad-gift search URL). That is far more than a restatement of the name. It stops short of explicitly distinguishing itself from the sibling search_gifts, which also handles keyword-style gift lookup, so an agent may still hesitate between the two.

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 imperative 'ALWAYS pass marketplace + locale' gives a hard calling rule, and 'keywords if no ASIN' implies input precedence, but the precedence lives in the schema rather than the prose. Nothing states when to pick this over search_gifts or when resolution is not appropriate. Usage is implied by the accepted input types rather than stated as a decision rule.

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