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

With no annotations, the description carries the full burden. It usefully discloses the proof-of-control prerequisite and the downstream effect (signed requests recognized as yours), plus credential and cost. It does not say what happens if the proof fails, whether rebinding replaces a prior key, or what is returned.

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 metadata tail ('Credential: key. Cost: Free. Source: PD1 §2A.') is compact and useful, but the leading 'I want my agent to...' framing is wasteful and duplicates the following sentence. The core action is not 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?

For a zero-required-parameter binding call with no output schema and no annotations, the agent gets the action, the prerequisite, and the effect. It still lacks failure behavior, rebinding semantics, and any description of the two parameters, so it is adequate but incomplete.

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 0% and there are two optional parameters, so the description must compensate. It refers loosely to 'add its operator's details' and 'register its operator,' which hints at operatorName/operatorEmail, but gives no format, validation, or requiredness guidance. Partial compensation only.

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 second sentence states a concrete verb+resource: 'Links a signing key after your agent proves it controls that key,' and adds the consequence 'Later signed requests are recognised as yours.' The leading first-person sentence is intent-flavored noise, but the tool's action is identifiable. It does not, however, distinguish itself from the adjacent sibling bind_provider.

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 precondition (the agent must prove control of the key) and one additional use case (registering an operator when none is named). There is no explicit when-not guidance and no routing to bind_provider or lodge_vault_key, which look like close alternatives. Usage is implied rather than spelled out.

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