reverse_dns_lookup

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It describes the batch capability, return format (all known hostnames), and handling of missing results. However, it doesn't mention rate limits, authentication needs, or error conditions that would be important for a network tool.

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 perfectly concise with three sentences that each add value: states the core purpose, describes batch capability, and explains return behavior. No wasted words and front-loaded with the main functionality.

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 network lookup tool with no annotations and no output schema, the description provides adequate basic information but lacks details about response format structure, error handling, and operational constraints that would be important for complete understanding.

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%, so the schema already documents the 'ips' parameter. The description adds context about batch lookups and what the parameter represents, but doesn't provide additional syntax or format details beyond what the schema provides.

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 with specific verbs ('perform reverse DNS lookups', 'find hostnames') and resources ('IP addresses'). It distinguishes from sibling tools like 'dns_lookup' and 'ip_lookup' by specifying the reverse direction and batch capability.

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 clear context for when to use this tool (to find hostnames from IP addresses with batch support). It doesn't explicitly mention when not to use it or name alternatives, but the context is sufficient for basic differentiation from siblings.

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