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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world, so the safety profile is covered. The description adds genuinely useful context by disclosing that a live token and its scopes are surfaced, which matters for an agent reasoning about credential exposure. It stops short of naming failure modes (e.g. invalid/expired token 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?

A single sentence that front-loads the subject (what is returned) and carries no filler. Every clause adds a distinct returned field.

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 is the only source of return-value information and it covers the key fields (user, tenant, token, scopes). For a zero-param read-only identity probe this is nearly sufficient; only error/expiry behavior is left unstated.

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 takes zero parameters, so the baseline of 4 applies; there is nothing for the description to disambiguate and it correctly avoids inventing any parameter discussion.

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 (returns) and enumerates the exact resources: the SKU.io user, tenant, token, and the token's scopes. No sibling tool covers identity/credential introspection, so it is trivially distinguishable from api_read, search_api, and the product/order tools.

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 name and description make the intended use (verifying which identity and scopes back the current connection) strongly implied, and no alternative tool could serve that purpose. However, the description never states when to reach for it or any precondition, so guidance is only implicit.

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