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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds the agency-key authentication requirement, which is useful, but says nothing about result volume or pagination behavior beyond what the schema already encodes.

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?

Extremely compact and front-loaded, with the constraint stated before the operation. The trailing 'GET /roles' adds little for an agent that already has the tool name, keeping it just short of perfect.

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 read-only list endpoint with full schema coverage and no output schema, the description supplies the essential auth constraint and endpoint. It is adequate, though naming the returned fields without an output schema leaves the return shape only partially described.

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 description coverage is 100% and all four parameters (page, order, per_page, role_type) are fully documented in the schema, including enums and defaults. The description adds no parameter-level detail, so the baseline 3 applies.

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 and resource ('list user roles') and names the fields returned, plus the 'agency key only' scoping constraint. It does not explicitly distinguish itself from the sibling whatconverts_get_role, which fetches a single role, so it stops short of a 5.

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 'Agency key only' qualifier is a genuine prerequisite that tells the agent when this tool is usable, but there are no explicit when/when-not statements and the single-role sibling (get_role) is never mentioned as the alternative for retrieving one role.

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