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 safety profile is covered. The description adds one useful non-annotation trait — 'Answers without an API key' (auth requirement). However, it doesn't disclose traversal limits (max hops), which relationship types are followed, or what a walk returns, which are meaningful behavioral traits for a graph-walking tool.

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?

Three short sentences, each earning its place: purpose first, then the auth note, then a concrete example. The description is front-loaded with the purpose and wastes no words. Not quite a 5 because the example could arguably be merged or trimmed, but it's efficient and well-ordered.

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 low-complexity tool (1 param, no enums, no nested objects, full schema coverage, safety annotations), the description is largely adequate. The only gap is the return format of a walk — with no output schema present, an agent is left to guess what the traversal produces. This minor omission keeps it from a 5.

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 input parameter is fully documented in the schema (domain, IP, ASN, or file hash). The description adds a concrete example call ('example.com'), which is a minor bonus but adds no semantic meaning beyond what the schema already states. The baseline 3 is appropriate given full schema coverage.

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 verb 'walk' plus 'graph from an indicator across its relationships' conveys a specific action (traverse relationships) on a specific resource (indicator graph). It distinguishes reasonably from siblings like whisper_identify (lookup) or whisper_explain (explanations) — 'walk' implies traversal. However, it never states what the output actually is (related indicators? paths? depth-limited results?), which leaves the purpose slightly underspecified.

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 an example call and notes 'Answers without an API key,' which hints at accessibility, but it never explicitly states when to choose this tool over siblings that also explore relationships (e.g., whisper_origins, whisper_variants, whisper_history). There is no 'use this when...' or 'for X use sibling instead' guidance.

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