dns_server_fingerprint

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

With no annotations, the description carries the full burden of behavioral disclosure. It explicitly describes the queries made (CHAOS class TXT records) and what information can be revealed, which is transparent about the operation. However, it does not mention potential side effects, such as the target server logging or blocking such queries, or the possibility that some servers return empty results. This is a minor gap but does not contradict the behavior 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 long, with no wasted words. The first sentence states the action and method, and the second provides illustrative context about what can be discovered. It is front-loaded and concise, covering all essential aspects without unnecessary detail.

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?

For a simple tool with one parameter and no output schema, the description is fairly complete: it explains the purpose, method, and expected outcome. It is missing a note about limitations, such as servers that do not support CHAOS queries or may return no records. However, given the low complexity, the description is sufficient for an agent to understand what the tool does and when to use it.

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?

The input schema already fully describes the single parameter 'nameserver' with an example ('8.8.8.8'). The description adds no new meaning beyond what the schema provides, so the baseline score of 3 is appropriate. It does not need to compensate for missing 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 clearly states a specific verb ('Fingerprint') and resource ('a DNS server'), and further specifies the method (querying CHAOS class TXT records) and the exact record names (version.bind, version.server, etc.). It distinguishes itself from sibling DNS tools like dns_lookup or dns_reverse by focusing on software/version identification rather than general DNS resolution.

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 gives a clear context for when to use the tool: when you need to identify the DNS software type and version. It does not explicitly mention alternatives or exclusions, but the specific technique (CHAOS class TXT records) implies a narrow use case, making it easy for an agent to select this tool over more generic DNS query tools.

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