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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), yet the description adds substantive context beyond them: required scope lots:read, own Fonciq API key in the Authorization header with token prefix format, billing identical to the HTTP route, and explicitly 0 $ / not billed. That is exactly the auth and cost information an agent needs before calling.

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 with the route and payload contents, which is good, but the full bilingual duplication roughly doubles the length and the billing point is restated redundantly ("identical to the HTTP route" and "0 $" in both languages). Every element is accurate but not maximally compressed.

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 single-parameter read tool with no output schema, the description covers what is returned, what is not performed, required scope, authentication mechanism, and cost. Nothing needed to invoke it correctly 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?

Schema description coverage is 100% and the single `lot` parameter is documented as "Lot number." The description's `{lot}` path template adds only positional context, no format or validation guidance. Baseline 3 is appropriate since the schema carries the semantics.

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 ("Stored profile of a Québec lot") plus the exact HTTP route, then enumerates the contents (cadastre, assessment-roll value in cents, stored index lines). The negative clause "Does not pull a new index" separates it from the index-request sibling, so an agent can pick correctly without opening schemas.

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 clear use context — retrieve an already-stored profile — and an explicit exclusion ("does not pull a new index", "returns no new document"). It implies the alternative (registre_index_request) without naming it, so routing is inferable but not spelled out.

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