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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is covered. The description adds genuine value beyond them by disclosing expected latency and the presence of data_as_of and is_stale fields for freshness judgment. It stops short of covering failure/error behavior or whether the upstream page can fail or be blocked.

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 purpose and fields, then latency, then return metadata. No filler, and each sentence adds information an agent would act on.

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?

The absence of an output schema is compensated by naming the key return fields and freshness metadata, which is well done. But for a two-parameter tool with no required fields and no schema descriptions, leaving the url/asin relationship entirely unexplained is a meaningful incompleteness.

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 0%, and the description never mentions url or asin at all. With zero required parameters, an agent gets no guidance on whether to supply a URL, an ASIN, both, or which one takes precedence.

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 (scrape) and resource (product page) plus the exact fields returned: price, stock, Buy Box seller, rating, review count. It is clear what the tool does, but it never contrasts itself with siblings like get_price or get_product, which cover overlapping data.

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?

"In real time" and the 3-10 second latency note imply this is the live-fetch option, which hints at selection versus cached siblings. However, there is no explicit when-to-use or when-not-to-use statement and no mention of get_price/get_product as alternatives.

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