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

With no annotations, the description carries the full burden, and it delivers: values are never exposed, timestamps may be null for older vaulted secrets, proof of npub ownership is required, and the field list itself is sensitive because it reveals integrations. This is rich behavioral context beyond the schema.

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?

Well front-loaded with the main purpose in the first sentence, followed by logically grouped detail about timestamps, non-exposure, cost, and auth. Slight redundancy exists between '(not values)' and 'Values are never exposed', and 'Free' is minor, but the overall structure is tight and readable.

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?

The tool has an output schema, so return shape is already covered. The description supplies everything else an agent needs: field-name semantics, timestamp nullarity, secrecy, sensitivity, cost, and authentication expectations. Nothing critical is missing for correct selection and invocation.

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 both parameters are already thoroughly documented, especially dpop_token's Nostr event format and constraints. The description adds only the security nuance that field names are sensitive, which is useful but not essential to understanding either parameter's meaning.

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?

States a specific verb and resource: 'List stored patron credential field names' with an explicit '(not values)' qualifier. This clearly distinguishes it from the many sibling tools that update, delete, or receive credentials, and from any tool that would return actual secret values.

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?

Gives concrete guidance on when to use it: 'use this to verify which fields are configured and how old each one is.' It does not explicitly enumerate alternatives or exclusion cases, but the context is unambiguous and sufficient for an agent to select this tool over credential-mutating siblings.

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