dns_cache_snoop

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

With no annotations provided, the description carries the full behavioral burden. It discloses the exact protocol behavior (RD=0, no recursion), the response interpretation (answer without recursion = cached), and the inference about recent domain visits. It would benefit from noting limitations such as TTL dependence or resolvers that ignore RD=0, but the core behavior is thoroughly described.

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 two sentences (45 words), front-loaded with the action, and every sentence earns its place: the first states the operation, the second explains how to interpret the result. No filler or redundancy.

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 a simple two-parameter query with no output schema, so the description must convey what the tool returns or how results are presented. The interpretation logic is explained, but the concrete return format (e.g., boolean, DNS answer, or status message) and edge cases (e.g., resolvers that ignore RD=0 or cache expiration) are not disclosed, leaving a meaningful gap.

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 100% — both 'domain' and 'nameserver' have clear descriptions with examples. The tool description adds no new parameter-level detail beyond the schema, so the baseline score of 3 applies.

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 uses a specific verb ('Perform DNS cache snooping') and precisely identifies the target resource (a nameserver) and the mechanism (non-recursive query with RD=0). It clearly distinguishes this from sibling tools like dns_lookup or dns_recursive_check by explaining the stealthy cache-probing technique and its forensic interpretation.

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 conveys a clear use case: revealing whether someone behind a resolver recently visited a domain by inspecting the resolver's cache. It implies when to use this tool (stealthy reconnaissance) and provides the expected result interpretation, though it does not explicitly name alternatives or state exclusions.

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