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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds valuable non-annotation context: it requires a Proof account and an authenticated session, with concrete steps ( /mcp authenticate or start_login). It does not describe what a negative result means or whether the check has side effects, but the auth disclosure is genuinely useful.

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?

Core purpose and usage are front-loaded in the first sentence, with auth prerequisites separated into a clearly labeled ACCESS block. The auth prose is slightly verbose but earns its place for a tool that fails without a session.

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 single-parameter read-only check with annotations covering safety and no output schema, the description supplies the missing prerequisite information (account and session requirements). Only the semantics of the boolean/result outcome are left implicit.

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 coverage is 100% with a single well-described `id` parameter, so the schema carries parameter meaning. The description adds nothing about the id's format or source beyond what the schema states; baseline 3 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?

States a specific verb and resource: checks whether stored DNS credentials can access a domain. This distinguishes it from the many domain/verification siblings such as verify_domain_with_credentials and check_domain_verification, though it does not name an alternative explicitly.

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?

"Use before triggering verification to confirm the credentials work" gives clear sequencing guidance relative to the verification flow. It provides no explicit when-not or named alternative, but the intended usage context is unambiguous.

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