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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, not open-world), so the lower bar applies. The description usefully adds non-obvious behavior: results are sorted cheapest-first and limited to current and previous models, excluding pre-orders/unreleased. It stops short of describing pagination or result-count behavior.

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, purpose front-loaded, no filler. The second sentence is dense with return-value detail but remains readable and earns its place given the absence of an output schema.

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 no output schema, the description correctly compensates by enumerating returned fields (retailer price, retailer, date, list price, verdict, Guide link). It omits any mention of the 'works_with' filter, the only notable gap for a 4-parameter tool.

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 all four parameters, and the description's category list duplicates it. It references the price and company filters but ignores the 'works_with' parameter entirely, adding little semantic value over the schema.

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 states a specific action (find what is on sale in a category) with enumerated categories and optional price/company narrowing, plus 'cheapest first' ordering. It clearly routes pre-orders/unreleased items to a named sibling, but never distinguishes itself from list_products, so an agent cannot tell these two apart from the text alone.

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?

It gives one explicit out-of-scope routing ('pre-orders and unreleased products are in get_release_calendar') and frames the optional filters as optional. It provides clear usage context but offers no guidance on when to prefer this over list_products or get_best_for.

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