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

Annotations already declare readOnly, idempotent, and non-destructive, so the safety profile is covered. The description adds two pieces of real value beyond that: the required auth scope (billing:read) and a data-boundary guarantee ('Never returns Stripe identifiers'), which tells an agent what it will not get back.

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?

Three short sentences, front-loaded with what the tool returns, followed by the auth requirement and the exclusion. No filler, no restatement of the title.

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?

There is no output schema, so the description carries the burden of describing the return shape, and 'what the organization is paying for' is vague about whether that means plan name, seats, price, billing status, or renewal date. The auth and exclusion notes help, but an agent still cannot predict the response structure.

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?

Zero parameters, so there is nothing for the description to disambiguate — baseline 4 applies. Implicitly scoped to 'the merchant's organization' rather than an arbitrary ID, which is consistent with the empty schema.

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 names the resource precisely — the merchant organization's paid subscription — which is distinct from siblings like get_billing_link or get_company. It reads as a noun phrase rather than an explicit verb+resource, but the intent (fetch current subscription/plan info) is unambiguous.

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?

No guidance on when to call this versus get_billing_link, get_company, or get_action_status, all of which appear in the sibling list and could plausibly be confused with billing/account queries. The caller must infer the trigger condition entirely.

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