get_invoices

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

Annotations already declare readOnlyHint=true and openWorldHint=true, covering the safety profile. The description adds no behavioral context beyond that – no pagination behavior, no result-size expectations, and no auth prerequisites for a list tool that could return many invoices.

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 padding; the scope ('full list of account invoices') comes before the parenthetical endpoint reference, which is a minor but essentially harmless addition. Efficient and unambiguous.

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 parameterless list tool with annotations covering safety and no output schema, the description is close to adequate, but it omits any hint about result volume or pagination, which matters for a 'full list of invoices' call. Adequate but with a clear remaining gap.

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 tool takes zero parameters (schema coverage 100% trivially), so per the rubric a baseline of 4 applies. There is nothing parameter-related for the description to compensate for.

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 clear verb and resource ('get_invoices') and scopes it as the full list of account invoices, which implicitly distinguishes it from get_invoice (single) and get_server_invoices. It does not explicitly name or differentiate against those siblings, but the 'full list' phrasing makes the scope legible.

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?

There is no guidance on when to use this tool versus get_invoice, get_server_invoices, or download_invoice. It simply asserts what it returns, leaving the agent to infer selection criteria from sibling names alone.

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