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

With no annotations provided, the description carries the burden of behavioral disclosure. It significantly adds context: keys never leave the agent, only the public signed identity is issued, and the output is deterministic. This goes beyond schema and helps an agent understand safety and side-effect boundaries, though it does not mention reversibility or authorization requirements.

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 compact and front-loaded, with every sentence carrying meaningful information: what the tool does, key outputs, security behavior, and even pricing. The structure is efficient — no filler or redundancy — and the parenthetical pricing is a minor, relevant addition.

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 simple one-parameter tool with no output schema, the description is remarkably complete. It covers the input type, the expected outputs, core behavioral guarantees (key custody, deterministic identity), and its role in the broader system. An agent has enough context to invoke it correctly without additional documentation.

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 baseline is 3. The description repeats the 'self-custody Base (EVM)' aspect already present in the schema, but it does not add new semantic meaning about the address parameter beyond what the schema states. It aligns with the schema without enriching it further.

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's function: provide a self-custody Base address and receive a signed, verifiable identity. It enumerates specific outputs (deterministic callsign, did:pkh, 0n1x-Verified credential) and distinguishes itself from siblings by positioning as 'the front door of the agent identity wallet.'

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 implies usage context through phrases like 'front door of the agent identity wallet' and 'give a self-custody address, get back...', but it does not explicitly state when to use this tool versus alternatives like rhinogent_verify_counterparty or onyx_attestation_verify. There is no exclusion or alternative guidance.

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