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

Annotations already establish readOnlyHint, idempotentHint, and destructiveHint=false, so the description's 'Read-only, no key required' reinforces the safety profile. It adds useful return-behavior context by stating that shared signals (common HS codes, certifications, country) are returned, though it does not cover error behavior or response structure details.

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 front-loaded with the core action and scope, then adds return semantics and read-only context. It is dense but each sentence carries useful information; it could be slightly tightened but wastes little.

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?

There is no output schema, so the description reasonably compensates by listing compared dimensions and shared signals. It is sufficient for an agent to call the tool correctly, though it could say a bit more about response shape or failure modes.

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%, so the schema already documents both the slugs array (2-4 suppliers) and the lang parameter. The description only repeats the 2-4 slug constraint and adds no additional meaning about parameter formatting or the lang behavior.

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 gives a specific verb and resource ('side-by-side comparison of 2-4 suppliers by slug') and enumerates the compared fields (identity, location, certifications, trade-fair count, employee range, year founded, HS code overlap, visibility). This clearly distinguishes it from single-supplier siblings like get_supplier and from search-oriented siblings like search_suppliers.

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 intended use case is implied by 'so you can summarize the trade-offs for a buyer,' but the description does not explicitly state when to use this tool versus alternatives such as get_supplier or get_similar_suppliers, nor does it give exclusions. This is workable context rather than explicit routing guidance.

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