New-car prices

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

Annotations already cover the read-only, idempotent, non-destructive profile, so the description's job is to add context beyond that. It does so by disclosing the row shape (price in Toman, provider types, daily change percent, 30-day trend) in the absence of an output schema, and warns that brand-wide queries can return many trims. Missing pagination/result-limit behavior and any note that history_days can extend beyond the default 30-point trend.

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?

Purpose is front-loaded in the first sentence and the sibling routing is packed into the last, so structure is good. There is minor waste and imprecision, e.g. the awkward 'how much is a zero Samand Soren today' phrasing and untranslated provider labels that could be trimmed or clarified.

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 4-parameter read tool with no output schema, the description supplies the return-field context an agent needs to interpret results. Remaining gaps are volume/pagination handling for brand-wide queries, which is flagged but not resolved.

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 schema already documents all four parameters, including the trim-needs-model constraint. The description adds one useful behavioral cue (pass model and trim to get a single trim instead of a long list) but no syntax or format detail beyond the schema; baseline 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 and resource with scope: 'Current price of every new-car trim of a brand or model on Bama's price list'. It immediately distinguishes itself from siblings by naming ba_market_stats (used market), ba_price_list (all brands) and ba_car_specs (technical data).

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 a concrete usage example ('how much is a zero Samand Soren today') and explicit routing rules: use ba_market_stats for the used market, ba_price_list to search all brands, ba_car_specs for technical data. It also tells the agent to pass model and trim to narrow a brand-wide query to one trim.

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