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

Annotations already declare destructiveHint=true, openWorldHint=true and idempotentHint=false, so the safety profile is covered. The description adds only the directional context that this records an incoming payment versus an outgoing one; it does not explain side effects such as altering the invoice balance or the duplicate-submission risk implied by non-idempotency.

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?

A single front-loaded sentence with no waste. It is efficient, though for a 6-parameter destructive mutation it borders on under-specified rather than optimally sized.

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?

This is a destructive, non-idempotent mutation with no output schema, and the description omits what an agent most needs: the effect on the invoice (balance/paid state), duplicate-payment risk, and the semantics of the status field. The annotations signal danger but the description does not fill the remaining 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 67% schema coverage, the schema itself documents date, notes, amount and invoice_id, while method and status rely on enums. The description contributes essentially nothing beyond the schema – it does not clarify the balance cap on amount, the meaning of status values, or the date default.

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 names a specific verb and resource (records a payment) and its scope (against an invoice), which clearly distinguishes it from list_payments or create_invoice without opening a schema. It falls short of 5 only because it never explicitly names a sibling.

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?

Beyond the phrase 'you received' implying an incoming payment, there is no when-to-use guidance, no prerequisites (does the invoice need to be sent/open?), and no pointer to alternatives like list_payments or update_invoice.

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