whoami

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

No annotations are provided, so the description carries the burden. It discloses the primary behavior (token validation and profile retrieval) and lists returned fields, which is reasonable for an identity check. However, it doesn't state whether invalid tokens cause errors, whether this is a safe read operation, or authentication requirements. As a benign, read-only identity tool with no annotations, a 3 is appropriate — adequate but with gaps around error handling and auth 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?

Two concise sentences, no filler, action-first structure.

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?

Given the tool's simplicity (0 params, no nested objects), the description is largely complete. The output schema exists, so return values are structurally documented, and the description supplements by naming the semantic fields. One could argue for more, like invalid-token behavior, but for a parameterless self-identity check, this is near-complete.

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?

The tool has 0 parameters, and schema coverage is 100% (trivially, since there are no properties). The description adds value by explaining what the tool returns (profile fields), which is the meaningful semantic content for a parameterless tool. With no parameters to document, the description's job shifts to clarifying the output contract, which it does.

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 tool validates the TechZone API token and returns the current user's profile with specific fields (name, email, roles, persona, API entitlement). It uses a specific verb ('validates') plus a clear resource ('TechZone API token'), and the output content is enumerated. It doesn't explicitly distinguish from siblings, but there are no overlapping sibling tools that do something similar, so the differentiation is inherent.

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 implies usage as a token validation/identity check, but there is no explicit guidance on when to use it vs alternatives, nor any context about prerequisites (e.g., being authenticated). There's no exclusions or when-not-to-use guidance. The purpose is clear enough that an agent could infer usage, but it leans on implication rather than explicit guidance.

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