All models of a brand

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

Annotations already declare readOnly, idempotent, non-destructive, open-world behavior, so the safety profile is covered. The description adds genuine context: the tool paginates over a fixed brand-scoped corpus and returns a compact field set including lowest shop price. It does not state how to detect the last page or how many pages exist, which is the one remaining behavioral gap.

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, each earning its place: what it does and returns, when to choose it, and where to go instead. The use case is front-loaded with no redundant repetition of schema fields.

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 usefully enumerates the returned fields, and all six parameters are documented in the schema, so an agent can call this correctly. The only shortfall is that pagination termination (total pages or model count) is never hinted at for a tool explicitly built for paging.

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% and each parameter already carries a description, including the brand-name-or-id hint and page size, so the schema does the heavy lifting. The description adds no parameter-level detail such as sort semantics or interaction between only_priced and price sorting. Baseline 3 applies.

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 — paging through all models Mobile.ir lists for one brand — and enumerates the returned fields (id, rating, year, screen, camera, lowest shop price). This is clearly distinguishable from sibling listing tools like mi_find and mi_search without opening a 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?

Gives an explicit trigger ('when mi_find's 100-row cap is too small or you want a brand's full line-up') plus explicit exclusions and their replacements ('Narrow by price or camera with mi_find instead'). It also routes single-model and comparison cases to mi_phone and mi_compare respectively.

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