check_record

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

Annotations already indicate readOnlyHint=true, idempotentHint=true, and openWorldHint=true. The description adds valuable context: it reads from authoritative and caching resolvers, reports agreement/disagreement, and explains output interpretations (empty values mean genuine absence; max_wait_seconds is remaining TTL). This enhances transparency beyond the annotations.

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 dense paragraph that covers purpose, parameter details, and output interpretation. It is relatively concise but could be more structured (e.g., bullet points or separate sections) to improve scanability. No wasted sentences.

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?

Given there is no output schema, the description adequately explains return values: 'Empty values mean the record is genuinely absent. When in_sync is false, max_wait_seconds is the largest remaining cached TTL — the wait before those resolvers refresh.' This, combined with parameter details and annotations, makes the tool self-contained.

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% (all three parameters documented), but the description significantly enriches meaning. For 'kind', it explains the derived query logic for spf/dmarc; for 'host', it clarifies which record types it applies to; for 'domain', it specifies formatting and Unicode handling. This goes well beyond schema basics.

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 clearly states the tool's purpose: 'Check whether a DNS change has landed: reads the record from the domain's OWN nameservers (cache-free) and from two public caching resolvers, and reports whether they agree.' This specific verb-resource pair distinguishes it from sibling tools like check_dkim_selector or validate_dmarc_record, which cover different DNS checks.

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 explains what the tool does and provides usage context (e.g., for checking DNS propagation after a change). It includes a caveat: 'This samples two resolvers, so never describe it as worldwide or as propagation coverage.' However, it does not explicitly state when not to use it or name alternative tools, leaving some ambiguity for the agent.

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