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

The description adds significant value beyond the annotations by specifying the exact format of the returned key (SPKI DER, base64) and the canonicalization method for verification. This fully discloses the tool's behavior.

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 very concise with two sentences, each conveying essential information without any redundancy. It is well-structured and 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?

Given that an output schema exists, the description is complete. It adds the critical canonicalization detail, which is necessary for understanding the tool's return value. No gaps are present.

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?

There are no parameters, and the schema coverage is 100%. The description does not need to add parameter information, so a baseline score of 4 is appropriate.

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 returns the server's Ed25519 public key in SPKI DER base64 format, used for verifying signal authenticity. It distinguishes itself from sibling tools which deal with markets, orders, and accounts, making its purpose unique and specific.

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 the tool is used when one needs to verify a signal's authenticity and timestamp, but it does not explicitly state when to use it versus alternatives. However, given the uniqueness of this tool, the context is clear enough.

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