Issue virtual card

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

Annotations only declare idempotentHint and destructiveHint=false, and the description adds real context beyond them: the card is created 'active' (immediately usable), and guardrails should be applied first, implying real spend risk. It does not mention the confirm/dry-run gate or the 365-day default, both of which live only in the schema.

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 sentences, zero waste, with the core action front-loaded and the workflow recommendation following. Every clause earns its place.

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 state-changing financial tool with no output schema, the description never says what an agent gets back (e.g., a card ID needed for the follow-up set_transaction_limit call) nor references the live-environment confirm gate. Annotations cover idempotency and non-destructiveness, so this is adequate but with clear gaps for chaining calls.

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 all five parameters are already documented including confirm, idempotencyKey, and expiresInDays. The description only adds a loose mapping for externalId ('one card per agent, workflow or vendor') and adds no new semantics for required financialAccountId; baseline 3 applies.

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 ('Issue a new active virtual card on a financial account') plus the intended granularity ('one card per agent, workflow or vendor'). An agent can distinguish this from sibling tools like get_payment_card, suspend_payment_card, or simulate_authorization without inspecting 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 explicit sequencing guidance: pair with set_transaction_limit and restrict_merchant_categories 'before using it', which names siblings and orders the workflow. It lacks a when-not-to-use clause (e.g., reuse an existing card vs. issuing a new one, or test vs. live mode) but the positive guidance is concrete.

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