List invoices

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description contributes genuinely new behavior — default sort order (newest first) and the exact cursor round-trip contract for pagination — which annotations do not express. It stops short of noting whether filters are ANDed, whether unpaginated results are possible, or what happens past the last page.

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 with no filler, and the operationally important pagination rule is stated directly. The first sentence carries no information the agent doesn't already have from the name, which is the only real waste. Structure is front-loaded with the high-value pagination note following immediately.

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?

Five optional parameters, one undocumented enum, and no output schema mean the agent has to guess at return shape and filter semantics. The description covers pagination but is silent on the four filtering parameters that make this more than an unfiltered dump. Adequate for a simple list call, but thin given the schema breadth.

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 80%, so baseline is 3; the cursor line largely repeats the schema's own "`next_cursor` from the previous page." The status enum has no per-value explanation and the customer/subscription filters are never mentioned in the description. No extra meaning is layered on top of the schema beyond clarification of the cursor field.

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?

"List invoices." is a near-verbatim restatement of the tool name and title, adding no scope, filtering capability, or object qualification. The second sentence adds real information but is about pagination rather than identity. An agent can infer the purpose from the name, but nothing distinguishes it precisely from siblings like retrieve_invoice or list_payments.

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?

No guidance on when to use this versus retrieve_invoice when an id is known, nor on how the status/customer/subscription filters should be combined. The cursor instruction describes how to page, not when to select this tool. The agent must infer usage entirely from the name and schema.

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