passkey_enable_virtual_authenticator

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

No annotations are provided, so the description carries the full burden of disclosing side effects. It mentions enabling a virtual authenticator and optionally injecting a credential, but does not say whether this alters the current browser session, requires a prior CDP connection, overwrites existing authenticators, or what happens when the optional credential is absent.

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?

A single, well-structured sentence conveys the core capability and optional behavior without wasted words. The main action is front-loaded, and the optional injection is clearly appended.

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?

With no annotations and no output schema, the description is too thin for an agent to confidently call this tool. It does not explain the context needed (e.g., a browser/CDP session), when the two optional-looking parameters are actually needed, or what observable effect the tool produces.

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%, so the schema fully documents rpId and account. The description does not add meaning beyond the schema, only implying that both relate to the stored passkey injection, which keeps this at the baseline 3.

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 a specific action ('Enables') and resource ('CDP WebAuthn virtual authenticator'), and adds the optional injection of a stored passkey. It is clearly distinct from the browser_* navigation/automation siblings, though it does not explicitly differentiate itself from passkey_save_registration or keychain_store_credential.

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 explains what the tool does but gives no guidance on when to use it versus alternatives like passkey_save_registration or keychain_store_credential. It also lacks prerequisites or any exclusions, so the agent must infer the intended context.

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