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

Annotations already cover read-only/idempotent/non-destructive, and the description adds substantial behavior beyond them: three verdict tiers with reasons and source dates, an Ed25519-signed verifiable receipt with key URL and verify endpoint, official open-data sourcing, and a 10/day free quota versus unlimited paid x402 access. That quota and cost model is exactly the kind of operational constraint annotations cannot express.

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 trigger and the checked-source list are well front-loaded, but the Ed25519 receipt sentence appears twice verbatim — a whole redundant sentence in a short description. Pricing/quota detail is also packed into the same block, so the structure is serviceable rather than tight.

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 carries the burden of describing returns, and it does: verdict level, reasons, source dates, plus contract count/total/buyers. Combined with the receipt verification story and quota, an agent has enough to call it. The missing pieces are the `lang` parameter and not-found/multi-match behavior.

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 75%, so the schema already documents neq and name; the description's 'Input: name, NEQ or RBQ licence number' reinforces that these are alternative identifier routes. However it omits the `lang` parameter entirely and never states that identifiers are mutually alternative or what happens with zero identifiers (required list is empty), leaving a real gap.

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 names the exact resources checked (RBQ licence status/categories/restrictions, RENA listing, environmental penalties, SEAO contract counts/totals/buyers) and the output shape (ok/review/blocking verdict). An agent can tell this is a multi-source Québec contractor due-diligence check. It does not, however, distinguish itself from plausible siblings like qc_licence or verify_business, so it stops short of a 5.

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 opening sentence gives a concrete decision trigger: 'Call before hiring, paying or subcontracting a Québec contractor.' That is a clear when-to-use context. There is no when-not guidance and no explicit routing to qc_licence or verify_business, so it is context without exclusions.

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