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

The description discloses critical behavioral traits beyond the annotations: the secret is returned only once, there is no recovery or identity, the code must be saved immediately and used as a Bearer token, the balance never pays out, accept_terms must be true, and the call is rate-limited/geo-blocked. This is far more than the annotations provide and is essential for safe invocation.

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?

Every sentence earns its place: purpose, secret handling, authorization usage, balance policy, terms requirement, next step, and rate-limit warning. It is dense but not bloated, and the core purpose is front-loaded.

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 one-parameter creation tool with an output schema available, the description covers the full lifecycle: what to do with the returned secret, how to authenticate, that there is no recovery, and what to do next (create_deposit). Nothing essential is missing for correct invocation.

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 0%, so the description carries the full burden. It explicitly explains the sole parameter accept_terms: it 'must be true' and links to the terms. This fully compensates for the missing schema descriptions.

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 opens with a specific verb and resource: 'Mint a prepaid wallet with no account behind it.' It clearly differentiates from sibling tools by stating this is the wallet-creation step and pointing to create_deposit as the funding follow-up. The agent can tell what this tool does and how it differs from related tools.

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?

It provides explicit workflow context: 'Then create_deposit to fund it,' and notes rate-limiting/geo-blocking parity with checkout. It does not explicitly state when NOT to use the tool or contrast with alternatives, but the workflow direction is clear enough for an agent to select it correctly.

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