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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the bar is lower. The description nonetheless adds genuine behavioral context by bounding the returned data (no personal identifiers), which prevents an agent from assuming it can harvest PII or user identity from this call.

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 short sentences with zero waste; the substantive return contract is front-loaded and the privacy caveat trails it appropriately. Nothing could be removed without losing information.

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?

There is no output schema, so the description carries the burden of describing the return values — and it does exactly that (role, tenant, granted scopes), plus a boundary statement. For a zero-parameter read tool this is fully sufficient to call correctly.

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 no parameters, which is the baseline-4 case. The description does not fabricate parameter semantics, and the empty schema plus additionalProperties=false is self-consistent with a zero-argument call.

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 precisely enumerates the resource contents (role, tenant, granted scopes) rather than restating the title. The negative scope ("Does not return personal identifiers") further sharpens what an agent can expect, and no sibling tool overlaps with identity/session introspection.

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?

Usage is implied by the nature of the tool — an agent checking its own identity/permissions — but the description never states when to call it, when not to, or what to do with the results. With no competing identity siblings and zero parameters, inference is easy, but no explicit guidance is offered.

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