check

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

Despite no annotations, the description discloses key behaviors: it registers new domains on first mention (a side effect), performs live DNS lookups, may read additional records, and writes explanations. This gives a good sense of the tool's side effects and internal logic.

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 moderately concise but contains poetic flourishes like 'Open the control room to watch, or read the report afterwards.' These add little practical value and could distract. The structure is clear but could be more direct.

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 explains the check and the side effect of registration, but does not specify the exact return value or output format. Since there is no output schema, the ambiguity about what the caller receives (e.g., a boolean, a report) leaves a gap. Also lacks guidance on when to use over siblings.

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%, so the baseline is 3. The description adds minor context about 'target' (a client, a known domain, or a new domain) and clarifies that dkim_selector should only be changed if not using Resend. This adds value but does not significantly exceed schema information.

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 the tool 'checks' a client or domain and clarifies that it performs DNS-based pass/fail checks. The verb 'check' and resource are clear, though the poetic phrasing partially obscures the exact nature. It is distinct from sibling tools like listing or auditing.

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 does not explicitly state when to use this tool instead of alternatives like 'client_status' or 'audit_all_clients'. It implies it is for quick DNS checks with no setup, but lacks direct comparison or usage conditions.

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