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

Annotations already cover idempotency and non-destructiveness, and the description adds useful context about what is checked (DNS TXT record or well-known file. However, with readOnlyHint=false, the description does not disclose any side effects the verification may have, such as updating listing state.

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 a single focused sentence with no filler; the action and target are front-loaded and the parenthetical adds specific, useful detail. It is concise, even though it omits deeper parameter and result information.

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 description says what to check and where, but because there is no output schema, return behavior is unexplained and parameter semantics are absent. The workflow prerequisite beyond 'from request_listing' is only implicit, leaving an agent to infer important details.

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?

All three parameters are required and have zero schema description coverage, and the description does not explain what 'reference' or 'listing_token' mean. The only hint is that the challenge comes from request_listing, which is insufficient for an agent to construct a correct call.

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 names a specific verb ('Check') and a specific resource (the domain-control challenge from request_listing), and goes further by naming the two concrete verification mechanisms: a DNS TXT record or a file at /.well-known/aci-verification.txt. This makes it easy to distinguish from sibling tools like approve_listing or get_listing_status.

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 phrase 'from request_listing' establishes clear workflow context: this is the verification step that follows a listing request. It does not explicitly list alternative tools or state when not to use it, but the intended place in the process is clear enough.

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