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

Beyond the readOnlyHint annotation, the description adds the default min_deal_score=60 threshold, the sorting direction (most to least underpriced), and the API key requirement. It does not conflict with annotations; no return format is described, but annotations already cover the safety profile.

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?

The description is short and front-loaded with the core function, but it mixes languages (English then French) and slightly restates the concept ('Les meilleures affaires du marché'). Still, it is efficient and each sentence adds something.

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?

Despite having 20 parameters, the high schema coverage and read-only annotation allow the description to remain high-level. It provides the feed's purpose, sorting, and auth requirement. It does not explain return values or pagination, but the schema covers parameter details and the output is a simple list feed.

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 90%, so the schema already documents parameters well. The description adds no new parameter meaning beyond what schema provides; it mentions min_deal_score default which is already in the schema. Thus 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?

The description clearly identifies this as an underpriced car deals feed, sorted by deal-score, and distinguishes it from general search tools by emphasizing it surfaces deals below market median ('nettement sous la médiane') and positions it as 'L'outil de pige des négociants' (dealer benchmarking tool). This is a specific verb+resource with clear differentiation from siblings.

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 provides clear context for when to use (finding underpriced deals, dealer benchmarking) and notes a prerequisite (Business API key). However, it does not explicitly name alternatives like pro_search or search_used_cars or state when not to use it, so it stops short of full exclusions.

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