Create a card

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

Annotations already indicate non-read-only, non-destructive, idempotent, and open-world behavior. The description adds that the card can be inserted with a letter, but doesn't expand on other behavioral traits (e.g., authentication required, response format, resource lifetime). No contradiction with annotations.

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 a single, concise sentence that conveys the essence of the tool without extraneous words. It is front-loaded with the action and followed by a clarifying example.

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?

Given the tool has 6 parameters, no output schema, and no return value description, the description is insufficient. It doesn't explain what the tool returns, how to handle errors, or how the card creation fits into a larger workflow. The annotations provide some guidance, but the description alone leaves important gaps.

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?

With 83% schema coverage, the schema describes most parameters. The description doesn't add meaning beyond the schema; it mentions the card's purpose but doesn't clarify how to specify 'front' or 'back' (e.g., file path or template ID). Baseline of 3 is appropriate.

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 'Upload a card' – a specific verb and resource – and explains what a card is (small printed insert). It distinguishes itself from sibling card tools like get/list/orders, though it could be more explicit about creation vs other actions.

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?

No guidance is provided on when to use this tool versus alternatives (e.g., postcards, letters). There are no prerequisites, context, or mentions of complementary tools, leaving the agent to infer usage from the name alone.

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