Compare products

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the description's job is to add behavior — and it does, disclosing that `specs` is filtered to rows whose values differ and returned in product order. That is non-obvious output semantics an agent could not infer. It does not discuss failure modes such as an invalid or missing product id, which keeps it below 5.

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 sentences with zero filler. The returned fields come first, the workflow guidance and the non-obvious filtering rule follow — properly front-loaded.

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 only one parameter, no nested objects and no output schema, the description carries the burden of describing the result — and it does list the compared fields and the differing-spec rule. It leaves the response's exact shape (how products are keyed, what happens with 2 vs 4 products) unspecified, a minor gap for this complexity level.

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 coverage is 100%, so the schema already documents the id formats, the 2-4 bounds and the array type. The description only reiterates the 2-4 range and adds the ordering note ('in product order'), which is marginal added meaning. 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?

States a specific verb and resource (compare products side by side) plus the exact dimensions returned (price, rating, seller count, differing specs). An agent can distinguish this from ss_search or ss_product without opening any schema.

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?

Explicitly positions the tool in a workflow: 'Use after ss_search to choose between candidates.' That names the prerequisite sibling clearly. It stops short of saying when not to use it (e.g., single-product lookups belong to ss_product), so it is strong context rather than complete routing.

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