recon_domain

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

No annotations are provided, so the description carries the full burden. It discloses that the tool is 'passive' (non-intrusive), has a 10-60s latency, and depends on external services (crt.sh). It mentions the output ends with a 'highlights' list, giving a sense of the return value. It does not mention rate limits or failure modes, but for a read-only aggregation tool, this is reasonably 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 two sentences with no redundancy. The first sentence packs the core functionality into a list without excess detail, and the second provides latency and an optimization hint. It is front-loaded with the purpose and scoping. Every word earns its place.

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 complex, aggregating many data sources, and the description covers its main components, latency, and a performance knob. It mentions the 'highlights' output but does not detail the full response structure. Since there is no output schema, a bit more on the output format could help, but the description is sufficient for an agent to decide when to call it. Missing edge-case behavior (e.g., invalid domains) is a minor 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?

The input schema has 0% description coverage, so the description must compensate. The description explains the 'include_subdomains' parameter indirectly by noting that passing false makes the run faster, implying it controls subdomain enumeration. The 'domain' parameter is self-evident from the tool name. It adds a performance nuance but does not fully describe the effect of include_subdomains on results (e.g., missing subdomain data). This is a partial compensation, hence a 3.

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 as a 'Passive overview of a domain in one call' and enumerates the data sources (whois, DNS, email security, TLS, HTTP headers, CT-log subdomains, ASN, reverse DNS, Shodan). This distinguishes it from the sibling tools, which each cover a single data source. The verb 'recon' and resource 'domain' are specific, and the aggregation is explicit.

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 when to use this tool: when a broad passive overview is needed in one call. It implies that specific tools (siblings) are for targeted queries, though it does not explicitly name alternatives. It provides a performance tip ('pass include_subdomains=false for a faster run') and a latency range (10-60s), which helps the agent decide. Missing explicit 'when not to use' guidance, but the context is clear enough for a 4.

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