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

Annotations already declare readOnlyHint and openWorldHint, so the description only needs to add useful context; it lists the ad attributes and the presence of seller_id, which is helpful. It does not cover error cases, authentication needs, or rate limits, but for a simple read-only operation this is not a major omission. No contradiction with annotations.

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 one efficient sentence: the purpose is front-loaded, followed by a colon-separated list of returned content. There is no filler or redundancy; every part adds useful information.

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 one-parameter read-only tool with an output schema and openWorldHint, the description is largely sufficient and even enumerates the expected output fields. It could be slightly stronger with explicit sibling routing or failure behavior, but nothing essential for a correct call is missing.

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?

The input schema already documents the only parameter fully: 'Identifiant numerique ou URL de l'annonce.' The description adds no additional parameter-level semantics or format guidance, so the baseline score of 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?

The description states a specific verb and resource: 'Detail complet d'une annonce' and lists the exact contents returned (description, photos, attributes, contact info, favorites, seller_id). This makes the tool's purpose unambiguous and distinguishes it from siblings: it returns full detail of one ad, not search results or seller 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?

The description implies the right context: use this tool when full details of a single ad are needed, identified by an ad ID or URL. However, it does not explicitly say when not to use it or mention alternatives such as search_ads for listing discovery or get_seller for seller-focused information.

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

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

The annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is established. The description adds the payload contents and the conditional professional-shop field, which is useful but does not disclose behavior for edge cases such as unknown sellers or missing professional data. With annotations covering the main behavior, a 3 is appropriate.

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 a single, compact sentence that front-loads the purpose and then lists the returned fields in a clear semicolon-separated structure. Every word earns its place and there is no filler.

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 one-parameter read-only lookup with full schema coverage and an output schema present, the description is largely complete. It covers the returned data well and the parameter description implies how to obtain the seller identifier. Explicit routing from get_ad could improve it, but is not a significant gap.

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 the single seller parameter is well documented in the schema as the seller_id from get_ad or an ad identifier/URL. The description itself adds no extra parameter-level meaning, so the baseline of 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?

The description clearly identifies the resource ('Profil d'un vendeur') and enumerates the specific data returned: anciennete, note, avis, response metrics, active listings, and professional shop details. It is distinguishable from get_ad and search_ads because it focuses on seller-level profile data rather than ads or searches, though it lacks an explicit action verb.

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?

There is no explicit when-to-use or when-not-to-use statement. However, the schema's parameter description says the seller is a seller_id returned by get_ad or an ad URL, which implies this is the follow-up tool for seller-level information. The usage context is present but not made explicit.

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

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

The description discloses meaningful behavior beyond annotations: it returns site totals, price statistics, per-ad fields, and a next_page pagination token. With readOnlyHint=true, the safety profile is already covered. It does not mention the file-writing behavior of export_format or the 300-ad threshold, but these are documented in the parameter schema, lowering the burden on the description.

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 sentences: the first states the primary action, the second summarizes outputs and pagination, the third routes to a sibling. There is no filler, and the most important information is front-loaded. Every sentence earns its place.

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 19-parameter tool with rich schema descriptions, an output schema, and annotations, the description covers the essentials: purpose, return contents, pagination, and a routing rule for ad details. The only notable omission is the export_format large-result caveat, but that is thoroughly covered in the schema, so the description remains sufficiently complete.

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 95%, so the parameters are already thoroughly documented in the input schema. The description adds no parameter-level semantics but notes useful returned attributes (etat, kilometrage, surface), which indirectly hints at filter keys. This meets the baseline for high schema coverage without requiring additional compensation.

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 opens with a specific verb+resource: 'Recherche des annonces sur Leboncoin' (search ads on Leboncoin), and further differentiates itself from siblings by explicitly directing ad-detail lookups to get_ad. An agent can immediately understand what this tool does and how it differs from get_ad and get_seller.

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?

The description clearly states a key alternative: 'Pour le detail d'une annonce (description, photos, vendeur), utiliser get_ad.' This gives an explicit condition for choosing a sibling tool. It does not explicitly mention when to use get_seller, but the distinction between searching and retrieving seller info is clear from context.

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