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

With no annotations, the description carries the full burden and does substantial work: it discloses what is correlated, that results are a 'suspected cluster' rather than an attribution claim, that returned field values are attacker-authored and must be treated as data (a prompt-injection warning), and it explains the semantics of the service_range field. It stops short of covering auth requirements, rate limits, or ordering behavior.

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 purpose is front-loaded in the first sentence, followed by interpretation caveats and a field note. It is dense but every sentence adds a distinct constraint; the only mild drag is the length of the enumeration and the trailing service_range explanation.

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 and no annotations, so the description must cover returns itself — and it does, naming the overlap categories and explaining the service_range column. What remains uncovered is result ordering and the effect of the limit parameter beyond what the schema states.

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 coverage is 100%, so both parameters are already documented in the schema; the description's note that the domain is 'resolved to its most recent detection, then correlated' largely restates the schema text. Its added detail (service_range semantics) concerns output fields, not inputs, so the baseline 3 holds.

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 a specific verb and resource — 'Find infrastructure and content overlap between a known phishing indicator and other phishunt detections' — and enumerates the correlation axes (IP, TLS cert, nameservers, favicon/screenshot, redirect target, naming pattern). It also distinguishes itself from the campaign tools by framing the output as observed technical overlap rather than attribution.

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?

Usage is implied: it is a pivot/correlation tool for a 'known phishing indicator', which tells the agent roughly when to reach for it. However, no alternative is named (e.g. get_campaign, analyze_url_deep) and no explicit when-not condition is given, so the agent must infer routing from sibling names alone.

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