yubikey-info

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

With no annotations provided, the description carries the full burden. It only lists the data returned (serial, firmware, etc.) but does not disclose that the operation is a read, any authentication needs, or error conditions like 'no YubiKey connected'. The behavior is implied but not explicit.

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, focused sentence of 17 words, conveying the tool's purpose and the type of information returned without any filler or redundancy.

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 lists the fields but does not specify the output format, structure, or error handling. However, the tool's scope is narrow and siblings provide context, making the description minimally adequate.

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 input schema has one parameter 'serial' with 100% coverage. The description adds value beyond the schema by explaining 'Omit if only one key is connected', providing situational guidance not present in the schema definition.

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 'Get detailed information about a connected YubiKey' and lists the specific details (serial, firmware, model, interfaces, applications), distinguishing it from sibling tools that focus on specific features like FIDO, OTP, or PIV.

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 provides no explicit guidance on when to use this tool versus alternatives (e.g., other yubikey-* tools for specific functions). It does not mention prerequisites, such as the YubiKey needing to be connected, or when to avoid using it.

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