invoices_email

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

Discloses key runtime behavior: emails are sent asynchronously, PDF attachment requires Pro, and non-client recipient addresses are rejected with a specific error. With no annotations present, this description carries the full transparency burden and does so well.

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?

Concise and front-loaded: action first, then usage note, then constraints. No redundant or filler content.

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?

Covers the essential preconditions (defaults, Pro, registered recipients) and side effects (async queue) for a 10-parameter tool with no annotations or output schema. It leaves little ambiguity about how to invoke or what to expect.

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 descriptions already cover all 10 parameters, and the description adds meaningful constraints such as recipient email registration and the Pro requirement for PDFs. It reinforces the default-template flow without restating every enum or default.

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?

Clearly states the action ('Send an invoice via email') and the resource, including optional PDF/XML attachments. The tool name and sibling context make it distinct from delivery note and receipt email tools.

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?

Provides actionable guidance to call invoices_email_defaults first for pre-filled subject/body, and spells out recipient restrictions. It does not explicitly contrast with delivery_notes_email/receipts_email, but the invoice-specific wording and constraints give clear context.

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