Compare Products

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

Annotations cover the safety profile (readOnlyHint) and open-world scope, and the description adds meaningful semantics beyond that: literal labels/values without inferred equivalence or unit conversion, explicit missing values and item errors, no ranking, and the caveat that prices/stock are cached observations rather than a checkout quote. That is a strong set of behavioral disclosures, with only minor gaps such as no mention of pagination or response shape (which the output schema likely covers).

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 short, front-loaded sentences that each carry a distinct constraint (scope, comparison semantics, output semantics, data freshness caveat). No filler or restatement of the tool name.

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?

An output schema exists, so return-value detail is not required, and the description is appropriately complete for a read-only comparison tool given its annotations. The remaining gap is parameter-level clarity around the ID input format, which neither the description nor the schema documents.

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 single parameter is a nested object wrapping a required array of numeric-string product IDs (pattern ^[0-9]{1,20}$). The description only repeats the 2–6 cardinality that the schema already enforces via minItems/maxItems, and does not explain the ID format, the nested 'query' wrapper, or how missing/invalid IDs surface as errors at the parameter level.

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 (Compare) and resource (specifications of products) with an explicit cardinality scope of 2–6 items, which implicitly separates it from sibling tools like compare_offers and compare_product_sellers. It stops short of naming an alternative, so the differentiation is inferable rather than explicit.

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?

Usage is implied by 'Compare specifications' and constrained by 'No ranking', but the description never says when to pick this over compare_offers, compare_product_sellers, or get_products_batch, nor what preconditions apply. No explicit when/when-not or alternative routing.

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