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

Beyond the read-only annotations, the description discloses the attribution selection logic (first-party, then curated, then third-party, not necessarily highest confidence), the fields returned for the strongest record and sources, the difference between `first_seen` and `ingested_at`, and the important caveat that `found: false` does not mean the indicator is safe.

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 front-loaded purpose, usage guidance, return semantics, and examples. It is somewhat verbose for a single-indicator lookup, and the first two sentences redundantly restate the same lookup action.

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, but the description thoroughly explains what is returned, including attribution, actor, source list fields, source count limits, and the not-found behavior. It also notes that country is only populated when the source provides it, which is the kind of operational caveat an agent needs.

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 the schema already documents the parameters and aliases. The description reinforces that `indicator` and `value` both work and gives example values, but its type hint list omits `email`, which the schema enum includes, so it adds only marginal parameter meaning and introduces a small omission.

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: look up a single indicator of compromise in the DugganUSA corpus. It explicitly scopes the tool to one IP, domain, URL, or hash and distinguishes its role from `search` by describing enrichment after search or direct single-indicator triage.

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?

It gives clear usage context: useful after `search` finds something, for attribution and cross-feed correlation, or directly during triage of a single indicator. It names the relevant sibling and implies single-indicator scope, but does not explicitly state when not to use this tool versus other siblings.

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