get_customer_subscriptions

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It adds the detail that the tool returns subscriptions 'of any status', which hints at scope, but it does not mention potential side effects, ordering, pagination, or output format. For a read-only get operation this is a minimal disclosure, but the lack of annotations makes this a significant gap.

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, compact sentence that delivers the essential information without any superfluous words. It is front-loaded with the primary purpose and follows with the parameter usage, achieving maximum clarity with minimal length.

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?

Given the tool's simplicity (one parameter, no output schema), the description is reasonably complete: it states what the operation does and the required input. However, it does not describe the structure of the returned data (e.g., array of subscription objects) or any edge cases like empty results or pagination, which an agent might need for correct handling.

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 schema describes external_id only as a string with no further meaning. The description compensates by clarifying it is the customer's external ID, which is essential for correct invocation. With 0% schema coverage, the description effectively explains the sole parameter, though it could add format constraints if 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 clearly states the tool's function with a specific verb (get) and resource (customer subscriptions), and adds scope detail ('any status') and the required identifier (external_id). It is unambiguous about what the tool returns, though it does not explicitly differentiate it from siblings like list_subscriptions.

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 provides no guidance on when to use this tool versus alternatives like list_subscriptions or get_subscription. It only states what the tool does, but never mentions conditions, exclusions, or scenarios where a different tool would be more appropriate.

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