whoami

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

With no annotations, the description carries the burden of explaining behavior. It indicates this is an introspection returning the current role and policy, but it does not explicitly state that the operation is read-only, what the response format is, or whether any policy evaluation side effects occur. This is adequate but not rich.

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 seven-word phrase with no filler or redundancy. The core identity/policy scope is front-loaded and every word earns its place.

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?

The tool has no parameters and a minimal schema, but no output schema exists, so the description should clarify the return shape. It names the two pieces of information (role and effective policy) but not their format, types, or nesting, leaving an agent to guess how to parse the response.

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 no parameters and the schema coverage is 100%, so there is no parameter burden for the description to carry. The baseline of 4 applies because there are zero parameters to document.

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 phrase 'Current agent role and effective policy' clearly identifies the resource as the agent's identity and policy context. It is distinct from the database-focused siblings (db_health, list_tables, run_select, etc.), though it lacks an explicit verb such as 'returns' or 'displays'.

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: an agent should call this when it needs to know the current role or effective policy. It gives no explicit when-to-use or when-not-to-use guidance and does not mention alternatives, but the tool is unique among the siblings, so the omission is less harmful.

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