Create an invoice

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

Annotations give idempotentHint=true; description reinforces that a job gets only one invoice and is safe to retry, adding error return types and actionable fixes. No contradiction, and adds value beyond annotations with error behavior.

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 a single dense paragraph that efficiently covers purpose, usage, retry safety, and errors. It is front-loaded with the core action and maintains focus, though slightly packed.

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 no output schema, the description covers key constraints (one invoice per job, accounting preference), error types, and preconditions. Missing success return value description but adequate for confident use.

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 cover both parameters (jobId and confirmed) with 100% coverage. The description adds conversational flow: mention job and amount, then set confirmed=true only after explicit confirmation, which is helpful context not in 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 creates an invoice for accepted/signed jobs, specifies which accounting systems (QuickBooks over Xero), and distinguishes from sibling tools like setell_mark_paid_offline by focusing on creating rather than marking paid.

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 tells the agent to first state job and amount, get explicit yes, then call with confirmed: true. It also notes safety to retry and lists expected error types with handling instructions, ensuring proper usage context.

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