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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), so the description earns credit for adding the substantive behavior: it compares against recorded daily history and emits a named flag for price manipulation. It does not say what happens when no history exists or how a stale/limited history is handled.

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?

Three tight sentences, zero filler, with the core action stated first and the flag detail and input provenance following in priority order.

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 values need not be explained, and the description covers purpose, provenance of the required ID, and the key flag. The one real hole is the semantics of the optional current_price parameter.

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%, so the description must compensate. It does explain where product_id comes from (responsible_alternatives), but current_price is left completely unexplained — whether it is optional, what happens if omitted, and whether it is compared against history. Half the parameters are still undocumented.

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: judge a sale price against recorded daily price history for a Shopify catalog product, plus the specific flag it can return ('raised_then_lowered'). That distinguishes it fairly well from siblings like verified_deals, though it never explicitly contrasts itself with them.

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?

Gives clear usage context ('works for Black Friday and Cyber Monday deals') and, importantly, routes the agent to the correct source for its required input: 'product_id comes from responsible_alternatives.' No explicit when-not-to-use or alternative tool is named, which keeps it below a 5.

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