reverse_dnsGet the PTR hostname for an IPv4 or IPv6 address. Useful for identifying mail servers, confirming that a crawler really belongs to the bot it claims to be, or adding a human-readable name to a raw log IP.
| Name | Required | Description | Default |
|---|---|---|---|
| ip | Yes | IPv4 or IPv6 address to reverse-resolve |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It explains the core behavior (reverse resolving an IP to a PTR hostname) and mentions IPv4/IPv6 support, but it does not disclose edge-case behavior such as what happens when no PTR record exists, error conditions, or rate limits. This is adequate but not exhaustive for a simple read-only lookup.
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: the first states the core function, the second lists use cases. It is front-loaded with the action and contains no extraneous content.
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 simple (one parameter, no output schema) and the description covers its purpose, supported IP types, and practical use cases. It lacks an explicit statement about the return value on failure, but overall the context is sufficient for an agent to select and invoke it correctly.
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 schema covers the sole parameter with a clear description and a pattern. The tool description restates that it works for IPv4 or IPv6 but adds no additional semantic detail beyond the schema. With 100% schema coverage, baseline of 3 is appropriate.
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 states precisely that the tool 'Get[s] the PTR hostname' for an IPv4 or IPv6 address. This clearly identifies the verb and resource and distinguishes it from sibling tools like dns_lookup (forward DNS) and ip_lookup (IP metadata).
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 provides specific use cases ('identifying mail servers, confirming that a crawler really belongs to the bot it claims to be, or adding a human-readable name to a raw log IP'), which gives clear context for when to use this tool. However, it does not explicitly name alternatives or state when not to use it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool targets a distinct resource and action. IP lookup, ASN, reverse DNS, blacklist, and VPN/proxy checks are clearly differentiated. Even the email tools focus on different mechanisms (auth vs breach).
All tools use consistent lower_snake_case, mostly following the <object>_<action> pattern. The few exceptions like my_ip and server_info still fit the overall style. There is no mixing of camelCase or inconsistent verb usage.
Fifteen tools is a well-scoped set for a comprehensive IP intelligence service. Each tool covers a unique capability without redundancy, and the count never feels bloated.
The surface covers the full lifecycle of IP investigation: lookups, reputation checks, batch processing, domain/DNS/email intelligence, and website security audits. Missing operations like SSL certificate checks are nice-to-have but not essential. The server_info tool also helps users discover capabilities.