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

It adds key behavioral details beyond annotations: the result is a draft (not final/sent), it creates exactly one line item from the deal's amount, and client_name defaults from company/title. It doesn't discuss failure modes or permissions, but the draft status and defaulting behavior are useful for an agent.

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?

Single sentence with no filler; front-loads the action and immediately states the key mapping behaviors. Every phrase contributes.

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?

The tool has 7 parameters and no output schema, and the description leaves five optional parameters semantically unexplained. It is sufficient for the minimal deal_id-only call but not for confident use of the full parameter set.

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 only 29%, so the description needed to explain the remaining parameters. It only clarifies deal_id (required, identifies the deal) and client_name (default), while notes, due_date, tax_rate, client_email, and payment_terms remain undescribed.

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'), a resource ('a draft invoice'), and a source ('from one of the caller's deals'), and clarifies scope with 'one line item' and default client_name. This distinguishes it from sibling create_invoice (blank invoice) and convert_lead_to_deal.

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 makes clear the intended input context: an existing deal belonging to the caller, with deal_id required. It does not explicitly name alternatives like create_invoice or when not to use, but the source constraint is enough to route selection in most cases.

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