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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is fully covered. The description adds one genuine behavioral fact beyond them — that a scan makes the phone prompt to save the contact — but says nothing about what the tool actually returns (image, URL, payload string) or its size/rate limits.

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?

Two short sentences with zero filler; the core action is front-loaded and the scan consequence follows briefly. Nothing needs to be trimmed.

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 5-parameter generator with full schema coverage and annotations covering safety, the description is adequate on purpose. It is thin on the return artifact, however: with no output schema, the agent still cannot tell whether it receives an image, a URL, or a code string, which is a real gap for a generator.

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%, and the enum's shape field is already documented with byte capacities, so the schema carries parameter meaning on its own. The description contributes no additional parameter guidance, which matches the baseline 3 for a fully documented 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?

States a concrete verb+resource: it produces a WIA Code wrapping a contact (business card) as a standard vCard, which implicitly separates it from the event/wifi siblings by payload type. It never names those siblings explicitly, so differentiation relies on the reader inferring from the content label rather than an outright contrast.

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?

There is no when-to-use statement, no prerequisites, and no mention of the alternative generators (generate_wia_code, generate_wia_code_event, generate_wia_code_wifi) that an agent must choose between. The only usage-adjacent sentence describes post-scan behavior on a phone, not when to call this tool.

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