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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds the inbound-only scope and the incremental 'since' polling behavior, but it does not disclose any additional behavioral traits such as empty-result behavior or network-specific limitations. This is adequate but not rich.

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 two compact sentences with no filler. It front-loads the core purpose and immediately gives the key usage tip, making it easy to scan and act on.

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?

With an output schema, a fully documented 4-parameter input schema, and annotations covering read-only/idempotent behavior, the essential context is complete. The only minor gap is not explicitly stating what a successful match looks like, but the output schema covers return values.

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%, and the schema already documents `since` as 'Cursor: last signature seen (position marker)' and `wallet` as 'Wallet to watch for inbound USDC.' The description reinforces the `since` semantics by saying 'Poll with the last signature as since,' but adds little beyond what the schema already provides.

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 uses a specific verb ('watch') with a clear resource ('a wallet for new inbound USDC') and a memorable purpose ('did the money land?' check). It also disambiguates this from sibling tools like pay by framing it as the post-payment verification step.

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 gives clear context for when to use the tool — after a payment, to check whether funds arrived — and provides an explicit polling pattern: 'Poll with the last signature as since to get only what's new.' It does not name alternatives or state when not to use it, but the intended usage is clear.

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