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

Annotations are thin (only destructiveHint=true), so the description carries extra weight, and it delivers the key behavioral fact: the created object is a draft that is not sent or emailed, validated by the named lifecycle alternatives. It does not address permissions/auth or explain the destructiveHint=true on a create operation, which is a notable omission.

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 the scope constraint front-loaded, plus a terse endpoint note. No filler; every clause earns its place.

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 17-parameter create tool with no output schema, the description covers creation semantics and lifecycle routing adequately, and the full schema covers parameter detail. It omits any note on return value or on the destructiveHint meaning, but the core call-time information is present.

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 100% across all 17 parameters, so the schema already documents each field (client_id hashed id, dates, discounts, line items). The description adds no syntax or format detail beyond that, so the baseline 3 applies.

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 specific verb (Create), resource (invoice), and a materially narrowing scope qualifier (DRAFT) for a client. An agent can immediately distinguish it from convert_quote_to_invoice or update_invoice.

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?

Explicitly says the invoice is not sent or emailed and names the two follow-up siblings, invoiceninja_mark_invoice_sent and invoiceninja_email_invoice, that handle sending. This is an explicit when-to-use and when-to-use-something-else statement.

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