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

With no annotations, the description fully discloses the challenge-response behavior, including that signing happens in the user's wallet and not in the tool, and that secrets must never be shared. It also clarifies that the tool returns a challenge rather than completing registration.

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?

Two sentences with clear front-loading of purpose and step, plus a critical security warning. Every sentence adds value.

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 step in a two-step flow, the description covers purpose, expected output, next step, and security context. The presence of an output schema means return format specifics are not required in the description.

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?

The schema provides only an 'address' parameter with no description (0% coverage). The description contextualizes it as the address whose key is used for signing, but doesn't explicitly define the parameter's format or details, leaving some interpretation.

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 this is step 1 of a self-service HOGSWAP API key registration, and explicitly distinguishes it from verify_registration (the next step). It identifies the action (registering an agent) and the output (a challenge).

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 explicitly instructs to sign the challenge and then call verify_registration, providing a clear workflow. It also warns to never pass mnemonics/private keys, establishing security-related usage boundaries.

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