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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and openWorldHint=false, so the safety profile is covered. The description's only added signal is the word 'visible', hinting at permission-scoped results, but it does not explain what visibility means, what happens if the entity is unknown, or result limits.

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?

Two short sentences, front-loaded with the core purpose and no wasted preamble. Minor redundancy between 'similar products' in the title and 'alternatives or comparable products' in the body keeps it from a 5.

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?

With an output schema present, return values need not be explained, and annotations cover the safety profile for this simple single-parameter read tool. The remaining gap is the undefined scope of 'visible' and no sense of result breadth, but nothing essential to invoking it correctly is missing.

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% and the single parameter is fully documented ('Entity name exactly as the user wrote it'), so the baseline of 3 applies. The description adds nothing about the parameter beyond what the schema already states.

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 ('Find') and resource ('visible alternatives or comparable products in the same category'), which is concrete enough to distinguish it from catalogue search or listing tools. However, it does not name a sibling tool it could be confused with, so it stops short of full differentiation.

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?

'Use for substitutes, alternatives, or similar items' restates the purpose as usage guidance rather than giving conditions, prerequisites, or when-not-to-use advice. No alternative tool (e.g. search_catalogue, get_product_master) is named for the case where the agent wants exact matches or broader search.

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