Subdomains from Certificate Transparency

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered; the description adds genuinely new context by naming the upstream sources, disclosing the passive/no-brute-force behavior, and noting a fallback path. It stops short of mentioning rate limits or result truncation behavior for large domains.

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?

One compact sentence plus a short qualifier: what it returns, from where, and the passive caveat all arrive immediately with zero filler. Nothing is redundant or padded.

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?

There is no output schema, so the description carries the burden of describing results; it says results are hostnames but not their shape, ordering, or handling of duplicates/truncation, and neither parameter is documented. Adequate for orientation, incomplete for correct invocation at scale.

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% across two parameters, with no prose in the description explaining either. The meaning of 'limit' (max 1000) and any default or impact on result ordering is left entirely undocumented, so the description does not compensate for the schema gap.

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?

Names the concrete resource (hostnames/subdomains for a domain) and the exact data source (Certificate Transparency logs via crt.sh with Cert Spotter fallback), which is far more specific than the sibling recon tools. No explicit verb (list/enumerate) and no direct sibling callout, so it stops short of a 5.

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?

'Passive: no DNS brute force' implies the intended mode of use and implicitly contrasts with active subdomain enumeration, but it never states when to pick this over attack_surface_report or security_headers, nor any prerequisites. Usage is inferable but not spelled out.

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