Find cheapest product

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

Annotations already declare read-only, idempotent and non-destructive, so the bar is low, yet the description adds substantial non-obvious behavior: the scan is deliberately bounded to relevance pages because the full catalogue is 'full of cheap accessories', matching requires all query words in the title with a documented fallback (any word, flagged with a `note`), 'suitable for ...' accessories are dropped, and sorting uses the buy-box price in Toman.

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 core capability and the follow-up recommendation are front-loaded and every clause carries information, but the single dense paragraph of matching mechanics is slightly run-on and would read faster as a short list of the filtering rules.

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 no explanation, and the description covers the non-obvious parts an agent needs: bounded scanning, word-matching rules with fallback, accessory filtering, price semantics in Toman, and the recommended next call. Nothing material is missing for correct invocation.

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 baseline is 3, but the description adds design intent the schema lacks: it explains why only the most relevant search pages are scanned (tying to `pages`) and why a min-price floor exists (dropping cheap accessories), reinforcing the min_price default documented in 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?

States a specific verb and resource with scope qualifiers ('cheapest in-stock products that really match a query, one flat list sorted by price'), which is clearly distinguishable from dk_search, dk_deals and dk_best_sellers. An agent can select this tool from the name plus the first sentence 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?

Gives an explicit trigger phrase ('Use for "cheapest X"') and a follow-up action with its rationale ('Then call dk_product on the winner: another seller may offer it for less'), which routes a multi-step workflow. It stops short of naming when not to use it (e.g. vs dk_deals or dk_search), so it is clear context without exclusions.

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