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

No annotations are provided, so the description carries the full burden. It discloses the return shape and that estimates derive from comparable listings, which is useful, but says nothing about accuracy caveats, behavior when comparables are sparse, or whether the call is purely read-only.

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?

A single front-loaded sentence with zero filler that names the verb, the scope, the output shape, and the methodology in one pass.

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 supplies the return structure (min/median/max). However, for a five-required-parameter tool with 20% schema coverage and no annotations, it leaves real gaps around input formats and failure modes.

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 only 20% (mileage in km is the sole documented field). The description adds no clarification for the four undocumented required parameters — notably 'fuel' is a free-form string with no enum, so format ('petrol' vs 'gasoline' vs 'diesel') is entirely ambiguous and the description does not resolve it.

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?

The description states a specific verb ('Estimate') and a precise resource ('fair price range for a specific car') and even names the output shape (min/median/max). It is clearly distinct from market-wide siblings like get_market_trend or get_price_history, though it never names an alternative explicitly.

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?

It implies the context ('for a specific car from comparable listings') but gives no explicit when-to-use guidance, no exclusions, and no routing to alternatives such as get_price_history for historical data. An agent must infer that this is the per-vehicle valuation path.

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