Latest shop prices market-wide

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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds non-obvious behavior beyond them: result de-duplication (one row per shop and model), the price currency (Toman), and the fact that memory/RAM variants live in `note` on the model page. It stops short of describing pagination limits or how far back the index goes, which keeps it from a 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?

Three short sentences, front-loaded with what the tool returns and its row granularity, then routing guidance, then units/caveats. No filler or restatement of the name beyond the necessary scope detail.

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?

For a 12-parameter, all-optional read tool with strong annotations and no output schema, the description covers purpose, alternative routing, units and dedup semantics. It leaves minor gaps: nothing about result volume or how 'newest' interacts with sort/descending, and no hint that page/page_size bound the response size.

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% and the schema already documents every parameter with defaults, enums and even province id examples, so the baseline is 3. The description adds marginal but real meaning: prices are Toman 'as posted by the shop' and variant distinctions are not separate filters but a `note` field, which prevents an agent from hunting for a memory/RAM parameter.

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 ('List the newest price rows that shops posted on Mobile.ir') plus the crucial granularity rule 'one row per shop and model'. It explicitly distinguishes itself from the sibling mi_shop_prices, so an agent can choose between them without opening either 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?

'Use it for "cheapest/newest Xiaomi prices in Isfahan" type questions' gives a concrete trigger scenario that maps onto the actual filter parameters (price, date, province). 'For one model's full offer list use mi_shop_prices' names the alternative and the condition that selects it.

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