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

Annotations declare the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false, openWorldHint=false), and the description adds meaningful behavior on top: it returns a job handle immediately rather than results, and the signed upload URL must be used before it expires. It does not discuss auth, rate limits, or retry/idempotency implications, but the async contract is well disclosed.

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?

Front-loads the core action and async return, then the input mode, then the numbered upload procedure. Every clause carries operational information; no filler.

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?

With no output schema, the description compensates by explaining that a handle is returned and results are fetched via get_job, and it resolves the zero-required-parameter ambiguity by defining the two valid input combinations. Nothing essential for a correct call is missing.

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%, so all five parameters are already documented in the schema, including the invoiceText-vs-file-reference exclusivity. The description reinforces the mutually exclusive input modes but adds nothing about outputFormat or the enum values, so the baseline 3 holds.

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 and resource ('Start an invoice-extraction job') and immediately clarifies the async contract by naming get_job as the retrieval sibling. An agent can distinguish this from create_invoice_upload_url and get_job without opening a schema.

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 states the two accepted input modes ('Pass invoiceText, OR filePath + bucket + mimeType from create_invoice_upload_url') and lays out the three-step local-file upload flow, including the ordered dependency on create_invoice_upload_url and the expiry constraint. Alternatives and conditions are fully spelled out.

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