wallet_topup

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

With no annotations, the description should fully disclose behavior. It mentions creating a session and returning a URL, but does not clarify session lifecycle, payment failure consequences, or idempotency. This is insufficient for an agent to fully anticipate side effects.

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, no redundant information. Efficiently conveys the core purpose and return value. Could be slightly more structured but remains highly concise.

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 simple tool with one parameter and an output schema, the description covers the basic idea. However, it omits details like whether amount_cents is in cents, if there is a minimum, or what the Stripe URL response contains. Adequate but not thorough.

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 only parameter amount_cents has 0% schema description coverage. The description does not add meaning like minimum value, allowed range, or currency. It merely restates the parameter name, providing no additional semantic value.

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?

Description clearly states the action (create a card top-up session) and the output (Stripe Checkout URL). It distinguishes from siblings like wallet_balance (read-only) and wallet_transactions (listing).

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 implies use when adding funds via card, but does not explicitly state when to avoid this tool or mention alternatives. As a single-purpose tool, the lack of explicit guidance is acceptable but not exceptional.

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