list-invoices

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

Without annotations, the description partially compensates by disclosing that Billforward has no native filter on invoice creation date and clarifying the period_start parameters' behavior. However, it does not explicitly state that the tool is read-only, nor does it mention pagination behavior like hard max limit or offset-based paging.

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 extremely concise: two sentences plus a note. Every sentence adds value, and the critical note about billing period is front-loaded. No redundant or extraneous text.

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?

Given no output schema and no annotations, the description covers core functionality and a key nuance but lacks details on pagination limits, default values (e.g., limit=10, offset=0), and sorting options. It is adequate but leaves gaps that the agent might need to infer from the schema.

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 100%, so baseline is 3. The description adds significant context beyond the schema by explaining that period_start_after/period_start_before filter by billing period start, not creation date. This prevents a common misinterpretation.

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 states 'List all invoices with pagination and sorting', which is a specific verb+resource combination. It distinguishes from sibling tools like get-invoice (singular) and list-payments/list-receipts (different resources) by focusing on invoices and including pagination/sorting details.

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 provides clear context for using the tool, including a note about the billing period filter behavior. However, it does not explicitly state when to use this tool versus alternatives like get-invoice or search, nor does it mention exclusions or prerequisites.

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