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

Beyond the readOnly/openWorld annotations, it discloses meaningful behavior: server-configured Associates tags are used rather than invented, and the resolution strategy differs by market (curated /dp on amazon.se and amazon.com, search deep-links elsewhere). It stops short of describing failure modes or what happens when inputs are ambiguous.

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-loaded with the core action and the one rule that matters most (always pass marketplace + locale). Some density is lost in stacked parentheticals, and the openAPI pointer adds little for an agent, but nothing is redundant enough to cut.

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 return value well and the critical required params, but leaves four optional parameters (preferSearch, category, occasion, asin vs url precedence) undocumented. Adequate to invoke, 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?

With 63% schema coverage, the description adds real meaning for marketplace (required, drives link strategy per storefront) and locale. But it never explains preferSearch, category, or occasion, and it references a `tag=` parameter that does not exist in the schema (additionalProperties: false), which could mislead a caller.

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 (resolve) and the exact input forms it accepts (ASIN, pasted /dp/ URL, keywords) plus the output shape (buyUrl, /dp link or romantic search). An agent can tell this apart from siblings like search_gifts or get_catalog without opening any schema.

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?

Gives a hard operational rule — "ALWAYS pass marketplace + locale for the user" — and a precondition for tagging (omit tag= until real IDs are set). It does not, however, contrast itself with the sibling search_gifts tool or state when a caller should prefer that path, which is the one remaining gap.

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