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

With no annotations, the description carries the full burden and discloses key behavior: it creates an asynchronous challenge, requires polling get_identity_challenge until terminal states (confirmed, denied, expired), and needs an authenticated Proof account. It also clarifies that start_login does not open this tool, preventing a common auth mistake.

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?

Three sentences, front-loaded with purpose, then agent usage, then access notes. Every sentence earns its place with no filler.

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 tool with no annotations and no output schema, the description covers the critical operational details: auth requirements, polling flow, and terminal states. It could go further by describing the non-ID fields in the initial response or error cases, but it is largely complete.

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 already documents all three parameters. The description adds context for why suspicious_channel matters, but does not add syntax or format details beyond what the schema provides.

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 states a specific verb ('Create') and resource ('Proof-Me cross-channel identity challenge'), plus scope ('for an enrolled challenger'). It does not explicitly distinguish this from creation siblings like create_confirmation or create_multi_channel_verification, so sibling differentiation is missing.

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?

It gives a clear usage scenario: the account holder approves/denies on a different channel than the suspicious contact. It also tells the agent to poll get_identity_challenge with the returned ID. However, it does not state when to prefer this over sibling creation tools.

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