get_payment_cardRetrieve payment card details—status, last 4, network, form factor, and expiration—without exposing the full card number.
Look up a payment card: status, last 4, network, form factor and expiration. Never returns the card number.
| Name | Required | Description | Default |
|---|---|---|---|
| paymentCardId | Yes | Highnote payment card ID |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, so the safety profile is covered structurally. The description adds genuinely useful context with the field enumeration and the explicit guarantee that the card number is never returned, which is the kind of security-relevant detail an agent cannot get from annotations. It does not mention error behavior for an unknown or expired card ID.
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?
Two short sentences with no filler; the returned-field list comes first and the non-disclosure guarantee follows. Every clause carries information an agent would act on.
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-only lookup with full schema coverage, the description covers purpose, scope of returned data, and the key data-protection boundary. The only meaningful omission is what happens on a missing or invalid card ID.
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 parameter is documented in-schema as a Highnote payment card ID, so the baseline is 3. The description adds no further meaning about the ID's format, source, or behavior when invalid.
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?
"Look up a payment card" gives a specific verb and resource, and the field list (status, last 4, network, form factor, expiration) makes clear what the call returns. It implicitly separates itself from mutating siblings like suspend_payment_card or close_payment_card, but never names or contrasts them explicitly.
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 when-to-use or when-not-to-use guidance, no mention of prerequisites (e.g., needing a valid card ID from another call), and no reference to alternatives among the many sibling card tools. Usage must be inferred entirely from the word "look up".
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.