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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description's real addition is naming what comes back (amount and paid flag), which matters because there is no output schema, but it says nothing about behavior for a nonexistent or invalid invoice id.

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 short sentences, front-loaded with the return content and followed by the endpoint. Nothing is wasted or padded.

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 single-parameter read with no output schema, saying what is returned (amount and paid flag) plus the endpoint is nearly sufficient. Only error/not-found behavior is left unaddressed.

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 coverage is 0%, so the description must carry the parameter burden. The path template GET /invoices/{Invoice-Id}/dueamount implies the single invoice_id parameter identifies the invoice, but it adds no format, origin, or constraint details beyond that implication.

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?

States a specific verb and resource: read the outstanding amount and paid flag for one invoice. This distinguishes it from repairdesk_list_invoices by being single-invoice, but it never mentions repairdesk_get_invoice, so the boundary with that sibling is left to inference.

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?

Usage is only implied by the name and endpoint – an agent can infer it is for checking whether an invoice is paid, but there is no explicit when-to-use clause and no statement telling the agent to prefer repairdesk_get_invoice when full invoice details are needed.

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