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

With no annotations provided, the description carries the burden of behavioral disclosure. It adds useful operational context: it is pay-per-use with a specific price in USDC on Base, and it clarifies expected input. However, it does not describe output format, failure modes, or how multiple invoices should be supplied.

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 exceptionally compact and front-loaded: purpose, input type, and pricing are all stated in a single efficient string with no filler. Every segment 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 batch extraction tool with no output schema and no annotations, key operational details are missing: how to pass many invoices, what the structured output looks like, and any cost/time implications beyond the flat price. An agent can grasp intent but not fully anticipate invocation behavior or results.

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?

The schema parameter description is generic ('service input'), so the description adds meaningful value by explaining that 'input' means invoice texts. This clarifies the expected payload beyond the schema, even though it stops short of specifying exact formatting.

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 states a specific verb ('extract'), a resource ('invoices'), and a scope ('many invoices' plus 'structured data + totals'). It does not explicitly differentiate from sibling tools like doc-extract or smart-document, but the batch/invoices focus is a meaningful distinguishing signal.

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 gives the input type ('invoice texts') but provides no guidance on when to use this tool versus alternatives, nor any exclusions. Sibling tools such as doc-extract and smart-document occupy a similar space, yet no selection criteria are offered.

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