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

Explains what the annotations cannot: why this is not read-only (every check leaves a sealed evidence record), the three verdict semantics with per-branch instructions, the ACF correction payload and retry budget, and the trust boundary ('never holds or moves money'). It also discloses the auth requirement (X-API-Key header), which is exactly the kind of operational context 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 purpose, then the call conditions, then verdict handling — a sensible ordering with little filler. The ACF spec URL and evidence-record asides are slightly dense, but each conveys information the agent needs to act on a non-MATCH response.

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?

There is no output schema, so the description carries the return-value burden — and it does, naming all three verdicts and the structure of non-MATCH responses (dimension, action, expected, actual, reason plus evidence pointer). Combined with the stated auth requirement, an agent has everything needed to call and react correctly.

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 100%, so the baseline is 3; the description earns an extra point by explaining the either/or relationship between 'mandate' and 'mandate_id' and summarizing what a mandate encodes (item, price limit, merchant rules). It says less about the cart sub-fields, but those are already documented in the schema.

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 — check a shopping cart against the customer's mandate before payment capture — and makes the temporal scope explicit ('before completing a purchase'). It is clearly separable from siblings like provecart_check_booking and provecart_check_reservation, which operate on different resources.

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 trigger ('Call this before completing a purchase') and spells out what to supply in each of the two modes. It doesn't explicitly contrast itself with the sibling check_* tools, but the resource difference makes the choice obvious, so this is clear context without formal exclusions.

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