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

With no annotations provided, the description is the only source of behavioral information. It notes 'Runs in the browser' and the credit coverage, but does not disclose how input is provided, what output format results, or any side effects. This provides some context but lacks critical operational details.

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 core purpose is stated in one sentence, but the description spends two sentences on credit pricing details, which is peripheral to tool selection. Still, it is relatively brief and front-loaded with the essential function.

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 tool with no parameters and no output schema, the description covers the basic function and access requirements, but fails to specify the expected input mechanism or output type. This leaves an AI agent uncertain about how to actually invoke the tool and what result to expect.

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 tool has zero parameters, and the input schema is an empty object, so schema coverage is 100%. The description adds no parameter-specific information, but no parameters exist to describe; the baseline of 4 applies for tools with no parameters.

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 opens with 'Receipt Scanner — Scan receipts with tight auto-crop optimized for small documents,' clearly stating the specific function and a distinguishing feature. This differentiates it from sibling scanner tools like mio_scanner_document or mio_scanner_batch.

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 implies use for scanning receipts but does not explicitly state when to choose this over other scanners or what alternatives exist. It only mentions 'scan receipts' and the auto-crop feature, so usage context is implied rather than explicitly contrasted with siblings.

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