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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so the agent knows this is a safe, read-only operation. The description adds value by stating it answers without an API key, a behavioral detail not present in annotations. It also shows an example call. However, it does not describe output format or limitations, which is acceptable given annotations cover the safety profile.

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 a single clear sentence followed by a concrete example call. It is front-loaded with the core purpose, uses no filler words, and each element earns its place. The example is concise and illustrative, making it easy for an agent to parse.

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?

For a simple one-parameter tool with no output schema and annotations covering read-only and open-world nature, the description is nearly complete. It explains what the tool does, provides an example, and notes the API key requirement. Minor gaps like output format are not critical given the tool's simplicity and the absence of an output schema.

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 100%, and the input field already has a detailed description listing accepted types (domain, IP, ASN, file hash) and an example. The description's example (example.com) mirrors the schema's example, adding little beyond what the schema provides. Baseline 3 is appropriate when the schema carries the parameter semantics.

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 action ('Assess') and the resource ('risk/policy posture of one or more indicators'), making the purpose specific and unambiguous. The inclusion of an example call ('example.com') further clarifies what the tool accepts. This distinguishes it from sibling tools focused on other operations like explain, identify, or walk.

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?

The description provides one piece of usage context: 'Answers without an API key,' which hints at when the tool is appropriate (no auth required). However, it does not explicitly state when to prefer this tool over alternatives or when not to use it. The purpose implies usage, but there is no routing to sibling tools.

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