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

With no annotations, the description carries the full burden and does add real value by enumerating what a run returns and disclosing the cost ('Flat 5 points per successful run'). It says nothing about authentication needs, rate limits, throttling, or error behavior on an invalid ID, so the disclosure is partial.

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?

Front-loaded verb and resource, with the return-field list and the points cost packed into the same compact block. The long field enumeration is justified by the absence of an output schema, so only minor trimming is possible.

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 simple one-parameter fetch with no output schema and no annotations, the description compensates well by naming the returned fields and the cost. It is only missing failure-mode and auth context, which is a modest gap for this tool class.

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%, so the single 'listing' parameter is already documented in the schema. The description's '(or listing URL)' merely restates the schema and adds no format or validation detail beyond it, making the baseline 3 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 ('Get') and resource ('leboncoin ad') and pins the input form to ID or listing URL, which separates it from the search/similar siblings like run_leboncoin_listings_similar. It stops short of explicitly naming those alternatives, so it is clear but not fully sibling-differentiated.

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 statement of when to use this tool versus run_leboncoin_listings_similar or other leboncoin siblings. The dual input form ('ID or listing URL') is the only implied guidance, leaving route selection to inference.

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