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

Annotations declare readOnlyHint=true, and the description reinforces this by stating 'Pure data fetch (no AI analysis)' and mentions 'when available' for history data, adding context about data availability and the lack of built-in analysis. It does not contradict annotations and provides useful behavioral context beyond the simple read-only flag.

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 description is reasonably concise, with the core purpose stated first and usage guidance following. It is not overly verbose, but the second sentence is a long, multi-clause instruction that could be more tightly structured. Every sentence contributes value, so it earns above average.

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?

Given the tool's simplicity (2 params, no output schema), the description compensates well by listing the key data fields returned (price, sales, reviews, etc.) and providing a detailed workflow for interpreting the data. It covers what the tool does, what data it returns, and how to use it, making it comprehensive enough for an agent to select and invoke correctly.

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 input schema already provides 100% description coverage for both parameters (asin and marketplace), so the tool description does not need to add parameter details. It mentions 'by ASIN' but does not elaborate beyond what the schema already states, so baseline 3 is appropriate.

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 clearly states 'Full raw data for a single Amazon product by ASIN' and explicitly notes 'Pure data fetch (no AI analysis)', establishing a specific verb (fetch) and resource (single product). It distinguishes from siblings like analyze_niche and analyze_product_set by focusing on a single ASIN.

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 description provides a clear 'How to use' section that frames the tool for product sourcing audits, including specific actions like demand trend analysis and GO/NO-GO decisions. However, it does not explicitly state when to use this tool over alternatives such as analyze_product_set, though the single-product focus is implicit.

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