Find cheapest groceries

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, open-world), so the description's added value is the ranking definition ('sorted by final price (price - discount)') and the scan scope (search results of open stores that deliver to the point). The caveat about delivery_fee/min_order hints that those costs sit outside the ranking, which is genuinely useful behavioral context.

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 short sentences, front-loaded with the core action, then the trigger, then the ranking and a practical caveat. Every sentence carries information; nothing is padding.

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 explanation is not required, and the description still usefully states the sort order. Combined with full schema coverage and annotations, the definition gives the agent what it needs to call the tool correctly; only the sibling boundary is unaddressed.

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 fully documents lat/long/limit/pages/query including the Iran bounding boxes. The description only loosely gestures at 'near the point' and adds no syntax or format detail beyond the schema, so the baseline of 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+resource ('find the cheapest in-stock offers for a grocery product near the point') with clear scope. It implies the grocery/market domain but never explicitly contrasts itself with the very similar sibling food_find_cheapest, leaving the agent to infer the boundary from the tool name 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 ('Use when the user wants the lowest price for an item') plus a follow-up rule about checking delivery_fee and min_order before recommending. It stops short of naming alternatives such as market_search or food_find_cheapest, so the when-not condition is absent.

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