passkey_register_options

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

No annotations are present, so the description carries the burden. It states the tool creates registration options but does not explain what the function returns (since no output schema) or that this is a preparatory step before passkey_register_verify. It is adequate but not detailed.

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 sentence of 10 words, efficiently conveying the tool's purpose without unnecessary words. It is appropriately front-loaded.

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 the low complexity (3 required params, no output schema), the description is somewhat complete but could be improved by indicating the return value (e.g., challenge, user info) or the next step in the passkey registration flow.

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% with clear descriptions for all three parameters (app_origin, project_id, access_token). The tool description adds no additional meaning beyond these schema descriptions, resulting in a baseline score.

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 'Create WebAuthn passkey registration options for the authenticated user' uses a specific verb (create) and resource (registration options), distinguishing it from siblings like passkey_login_options and passkey_register_verify.

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 guidance on when to use this tool versus alternatives such as passkey_login_options or passkey_register_verify. No context about prerequisites or workflow order is given.

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