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

Beyond the readOnlyHint annotation, the description adds meaningful context: the keys are public and keyless (no credentials required), and they include derivation paths and validity windows. This gives the agent a better sense of what to expect without needing additional discovery. No contradiction with the annotation.

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 no redundancy. The first sentence states what the resource is, the second gives the intended use and access characteristics. Every word earns its place.

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 parameterless, read-only resource with no output schema, the description is fully sufficient. It covers the resource content, its provenance, and the intended application (offline verification). No additional context is needed for the agent to invoke or use it correctly.

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 input schema has zero parameters, so there is nothing for the description to add. The baseline of 4 applies because with no parameters, the schema is trivially complete and the description need not explain any parameter details.

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 identifies the tool as providing Ed25519 public keys that sign DomainDrift observations, including derivation paths and validity windows. It also states the intended use case (verification), which clearly distinguishes it from sibling tools like lookup_domain or resolve_receipt.

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 explicitly says when to use the tool ('verify receipts and signed records offline') and notes that it is public and keyless, implying no authentication is needed. It does not mention when not to use it or name alternatives, but the context is clear enough for the agent.

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