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

With no annotations, the description must carry safety and side-effect disclosure. It clearly says this is a listing operation, that only metadata is returned and secrets are not exposed, and that a session/login prerequisite must be satisfied. This is useful behavioral context, though it does not mention response pagination or rate limits.

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 two short sentences with no filler. The core purpose is front-loaded, and the authentication prerequisite is placed as a clearly labeled ACCESS note.

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 no-parameter list operation, the description covers what is listed, the non-secret nature of the return, and the authentication prerequisite. A fuller return-shape example would help since no output schema is provided, but the description is sufficient for basic 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?

The tool has zero parameters, so the 100% schema coverage makes the schema sufficient. The description adds no parameter detail because none is needed; by the 0-parameters baseline, this 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 states a specific verb ('List'), a precise resource ('all stored DNS provider credentials'), and a scoping context ('for the authenticated account'). It also distinguishes itself by clarifying it returns metadata, not secret values, which differentiates it from credential-creation and provider-connect tools.

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 ACCESS note gives clear when-to-call context: a Proof account is required, and the agent is told to authenticate or run start_login and then retry. It does not explicitly contrast with list/get_dns_providers or check_domain_credentials, so it stops short of a full alternatives comparison.

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