passkey_login_verify

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

No annotations are provided, so the description carries the full burden. It states the tool 'verifies' and 'returns a session', but omits details such as idempotency, failure outcomes, or whether it mutates state. For a security-sensitive operation, this is insufficient.

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 12-word sentence that conveys the core purpose without extraneous words. It is well-structured and 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 lack of output schema and annotations, the description should provide more context about the returned auth session and expected input behavior. It is minimally adequate but lacks details about error states or prerequisite steps.

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 coverage is 100%, so the description adds little beyond what is already defined. It hints that 'response' is a browser assertion and that 'challenge_id' comes from passkey_login_options, but does not elaborate on usage or format. This meets the baseline but does not excel.

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 the tool verifies a browser WebAuthn assertion and returns an auth session, which matches the name 'passkey_login_verify'. However, it does not explicitly contrast with sibling tools like 'passkey_register_verify' or mention that this is for login specifically.

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. It does not mention prerequisites (e.g., needing a challenge from passkey_login_options) or exclude cases where registration verification is needed. Given the presence of multiple passkey-related siblings, this omission is significant.

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