dkim_check

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

No annotations are provided, so the description carries the full burden. The verb 'look up' indicates a read-only operation, and the default DNS server is disclosed, but there is no explicit statement that this is safe/non-mutating, nor what happens if no DKIM record exists (e.g., return type, errors). The behavior is simple but not fully transparent.

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, front-loaded sentence followed by a concise parameter list. No wasted words; every line provides useful 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 tool is simple and the description covers the essential inputs and examples. An output schema exists, so return values are not required in the description. However, it lacks explicit sibling differentiation and edge-case behavior (e.g., record not found), which would make it more complete.

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 0%, but the description fully compensates by clearly explaining each parameter with examples: domain ('example.com'), selector ('selector1', 'google', etc.), and dns_server (default '8.8.8.8'). This adds real meaning beyond the bare schema.

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 action ('Look up a DKIM record') with a clear resource (DKIM record) and scoping (domain + selector). It naturally distinguishes from siblings like spf_check and dmarc_check because it targets DKIM specifically.

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 usage context is implied by the purpose and examples (e.g., selectors like 'google', 'default'), but there is no explicit guidance on when to choose this tool over alternatives or when not to use it. For example, it does not mention that SPF or DMARC checks would be handled by sibling tools.

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