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

No annotations are provided, so the description carries the behavioral disclosure burden. It clearly indicates a read operation ('Return') and discloses the auth requirement ('Requires a Sorqen key'). However, it does not describe failure modes, how the key is supplied, or the exact structure of 'limits and entitlements', leaving some ambiguity.

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 carry the action, scope, auth requirement, and usage trigger with no filler. The most important information is front-loaded, making it easy for an agent to parse quickly.

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 zero-parameter tool, the description covers the essential context: what it returns, that a key is required, and when to use it. It would benefit from explaining how the Sorqen key is provided or what happens without one, but the core invocation context is present.

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 zero parameters, so there is no parameter documentation burden. The description accurately focuses on the return value rather than inputs. A baseline of 4 is appropriate since parameter semantics are not applicable.

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 states a clear action and resource: 'Return the caller plan, limits and entitlements.' This distinguishes it from general catalog tools like describe_plans by focusing on the caller's own plan. It does not explicitly name sibling distinctions, but the title and phrasing make the purpose clear.

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 description gives a concrete use condition: 'Use when a field is locked or a limit is reached.' This tells an agent when to invoke the tool. It does not name alternatives or explicit when-not-to-use cases, but the trigger scenario is helpful and specific.

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