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

With no annotations provided, the description carries the full behavior disclosure burden and largely succeeds: it discloses the 1-credit cost, that empty results and failures are never charged, and the free 24h cache-hit behavior with default always-fresh. It doesn't address auth or rate limits, but the economically important traits are transparent.

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?

Four sentences with zero filler: purpose, payload scope, exclusion, and cost/caching behavior in order. Every sentence earns its place and the most decision-relevant facts are front-loaded.

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 5-param tool with no output schema or annotations, the description covers scope, exclusions, output-content hints, pricing and caching, while the schema covers all parameters at 100%. Only auth/rate-limit behavior and the exact return structure go unspecified, which is a minor gap for this tool family.

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%, with url, cache, limit, cursor and marketplace each fully documented, so the baseline 3 applies. The description reinforces cache=true and the credit cost but adds no parameter syntax or format details beyond the schema — appropriate given the rich schema.

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+resource: fetching third-party seller storefronts via /sp?seller= or /s?me=. Enumerates the payload (ASIN + canonical /dp URLs, price, badges) and explicitly excludes influencer /shop/{handle} pages, sharply distinguishing it from potential sibling tools.

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?

Provides clear context: it targets Amazon seller storefronts and excludes influencer /shop pages, with the schema reinforcing the URL-platform-match requirement. No alternative tool is named for influencer storefronts, so the 'when-not' guidance is present but the routing alternative is left for the agent to infer.

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