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

Annotations already declare openWorldHint=true and destructiveHint=false, but the description adds genuine behavioral context: unstable backlink/network sources are disabled until verified, and missing data must not be read as clean risk. The caveat is valuable interpretation guidance not present in any structured field. It still doesn't explain why readOnlyHint is false for what reads like a lookup.

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?

Two tight sentences, front-loaded with the core action and followed by an interpretive caveat. No padding or redundancy.

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?

With no output schema, the description should convey what the check returns, but it only alludes to 'risk signals' and 'clean-risk findings' without describing the result shape (score, status list, verdict). The disabled-source and missing-data caveats partially compensate, but the return semantics remain unclear.

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% and the single 'domain' parameter has no schema description, so the description carries the burden of clarifying it. It adds nothing about expected format (bare domain? URL? IDN?) or validation, leaving the parameter effectively undocumented.

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?

States a specific verb ('Check') plus resource ('domain risk') and enumerates what it examines: registry RDAP status and reported risk signals. Clear enough for an agent to distinguish it as a risk-assessment tool, but it never explicitly contrasts itself with siblings like analyze_domain_value or get_domain_history.

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 when-to-use guidance and no comparison to the four sibling tools, which include closely related 'analyze' and 'history' operations. The agent is left to infer that this is the risk-signal check, with nothing on exclusions or prerequisites.

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