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

The readOnlyHint annotation already establishes the safe-read behavior. The description adds useful status semantics and notes that an approved result includes invoice_id and pay_link, which is valuable extra context absent from structured fields. It does not cover polling behavior, auth needs, or rate limits, but the annotation lowers the disclosure burden.

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 efficient sentence that front-loads the resource and includes the key status values. Every clause contributes either scope or return-value information.

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 read-only tool with one required parameter, the description covers the main statuses and the approved response shape. However, it omits how to obtain approval_id and gives no guidance on polling while pending or interpreting rejected versus failed. With no output schema, a little more completeness would help.

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 must explain approval_id but does not. It implies the approval request originates from create_invoice returning pending_approval, but never explicitly says that approval_id comes from that response or how to obtain it. The single parameter is therefore only indirectly inferable.

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 identifies the resource: the approval status of an invoice request queued by the seller's API key policy. It also links the tool to create_invoice returning pending_approval, which helps an agent distinguish it from invoice retrieval tools. However, it does not explicitly contrast with sibling tools such as get_invoice or check_payment.

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 a clear trigger for use: after create_invoice returns status pending_approval. It does not state when not to use the tool or name alternatives, but the operational context is explicit enough for correct selection.

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