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 fully covered. Beyond that the description only says describe_operation supplies native request schemas — no pagination behavior, no result shape, no scope of what roles are returned. It adds almost nothing behavioral.

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?

It is short, but the identical sentence 'GET /api/roles.' appears twice, and an internal operation ID is surfaced where it adds no decision value. Brevity here comes from under-specification rather than efficiency.

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?

No output schema exists and the parameters are undocumented, so the description needed to explain the query semantics and expected result. Instead it defers entirely to describe_operation, leaving the agent unable to construct a correct query payload from this definition alone.

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?

There are two parameters (a free-form 'query' object with additionalProperties and an empty 'params' object) at 0% schema description coverage, so the description carries the full burden of explaining them. Instead it says nothing about query keys, filtering, or pagination — the free-form query object is completely unexplained.

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 is essentially a tautology: it repeats the endpoint 'GET /api/roles' twice and adds only an opaque operation ID. The only real signal comes from the tool name and title, not from the description text, so an agent learns nothing about what a 'role' payload contains or whether this is a list operation with filtering.

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?

It points at describe_operation as the source of native request schemas, which is a minimal routing hint, but there is no statement of when to call this versus siblings like describe_operation, execute_read, or get_roles_by_id. The agent must infer that this lists roles and the *_by_id variant fetches one.

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