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

Annotations already cover safety (readOnly, openWorld, non-idempotent, non-destructive), so the bar is lower. The description adds genuinely new behavior: a nonce-based two-phase protocol where the first call yields a dig to run and the second returns observed resolver details plus a signed TXT. It doesn't mention rate limits or auth requirements.

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?

Compact and front-loaded: the when-to-use condition leads, followed by the two-call sequence. The parenthetical field list is dense but each item earns its place as return-value preview.

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?

With no output schema, the description usefully enumerates what the second call returns (resolver address, transport, DO/CD flags, EDNS size, cookie, ECS, case, arrivals, signed TXT) and explains the two-phase flow. Only the first call's output (the dig command) is left slightly 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% and both the schema and description say the nonce comes 'from the first call', so the description adds no syntax or format detail beyond the structured field. Baseline 3 for a fully documented single parameter.

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 purpose: proving what the resolver sends, and outlines the two-call flow. It hints at a difference from plain dig/trace by framing it as a 'receipt', but never names a sibling to differentiate against.

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 when the person wants proof of what their resolver sends' gives a clear triggering condition, and the two-step ordering is spelled out. It stops short of saying when to prefer this over dig, trace, or alias_chain.

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