send_invoice

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

With no annotations, the description transparently discloses irreversibility, pre-send confirmation requirements, error scenarios (403, 422, 409), idempotency key usage to prevent duplicates. This fully covers behavioral traits.

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 concise (few sentences), front-loads the core purpose and irreversibility, then provides structured guidelines. No redundant phrases; every sentence adds value.

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 7 parameters, no output schema, and no annotations, the description covers purpose, irreversibility, pre-send confirmation, parameter usage, error handling, and idempotency. It is highly complete for the tool's complexity.

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 has 0% description coverage, but the description adds crucial context: parameters like subject/body/to/cc/bcc are normally omitted and included only when user explicitly overrides; idempotency_key is optional and auto-generated; invoice_id is required. This adds significant meaning beyond the schema.

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 the tool sends an invoice email to a customer and that the action is irreversible. It uses a specific verb ('send') and resource ('invoice'), distinguishing it from siblings like send_quote.

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 explicit guidelines: confirm destination email, amount, and attached PDF before sending; normally omit subject/body/cc/bcc; error handling with status codes and checks (e.g., get_tenant_settings). It lacks direct comparison with siblings but implies it's for final sending.

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