whois_lookup_by_asn

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

With no annotations provided, the description carries full burden but offers minimal behavioral insight. It mentions pagination and source filtering, which are useful, but doesn't disclose critical traits like rate limits, authentication needs, error conditions, or whether this is a read-only operation. For a lookup tool with no annotations, this is inadequate.

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 well-structured with clear sections (Args, Returns) and uses bullet-like formatting. It's front-loaded with the core purpose. However, the 'Returns' section is somewhat redundant given the output schema, and some sentences could be more tightly integrated.

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?

Given 3 parameters with 0% schema coverage and an output schema, the description partially compensates by explaining parameters but lacks behavioral context. It doesn't cover error handling, rate limits, or sibling differentiation. The output schema reduces need for return value details, but overall completeness is moderate.

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 0%, so the description must compensate. It successfully explains all 3 parameters: asn (ASN number), page (for paginated results), and source (with specific WHOIS sources listed). This adds meaningful context beyond the bare schema, though it could detail format constraints like ASN ranges.

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 performs a WHOIS lookup by ASN, which is a specific verb (lookup) and resource (WHOIS records for ASN). It distinguishes from siblings like whois_lookup_by_domain and whois_lookup_by_ip by specifying the ASN parameter type. However, it doesn't explicitly contrast with get_asn_info, which might provide overlapping functionality.

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?

No guidance is provided on when to use this tool versus alternatives like get_asn_info or other WHOIS lookup siblings. The description mentions parameters but doesn't explain use cases, prerequisites, or exclusions. This leaves the agent without contextual decision-making help.

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