create_card

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

The description discloses important behavioral traits: policy enforcement and possible return statuses (denied_by_sentinel, approval_required_by_sentinel). However, it does not mention side effects like wallet deduction or idempotency, and no annotations are provided. The description is adequate but incomplete.

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 description is very concise (one sentence plus a note), but it is under-specified given the tool's complexity (8 parameters, no annotations). It is not overly verbose, but the brevity sacrifices completeness.

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?

The description lacks essential details: no success response, no explanation of parameter differences (e.g., single_use vs multi_use), and no information on expiration or scope_preset. With no output schema and no annotations, the description is insufficient for an 8-parameter creation tool.

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?

The description adds no parameter-level information beyond the schema. With 50% schema coverage, the description fails to compensate for undocumented parameters like 'type', 'expires_at', 'amount_cents', and 'scope_preset'. The mention of 'funded from the wallet' loosely relates to 'amount_cents', but this is not explicit.

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 clearly states the action ('Mint a new virtual card') and the resource ('funded from the wallet'). It is specific and distinguishes from sibling tools, which are all list, check, close, or buy operations, so there is no ambiguity.

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 description provides no explicit guidance on when to use this tool versus alternatives. While it implies creation, it does not mention prerequisites (e.g., wallet balance) or when other tools like 'check_balance' or 'list_cards' should be used instead.

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