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

With no annotations, this description carries the full disclosure burden and does so well: it reveals the pricing/charging model, that charges pause on withdraw, and that checkout/portal return URLs for a human to act on. The explicit prohibition on entering payment details is an important behavioral constraint.

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 packs a lot into two sentences, with the key summary up front and no filler. The pricing detail is somewhat tangential to a single call, but it is relevant enough to avoid being marked as unnecessary.

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 simple two-parameter tool with no annotations and no output schema, the description covers invocation, action semantics, and authorization boundaries. The only notable omission is the exact shape of the `status` response, but it is not required to call the tool correctly.

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 already documents both parameters fully (100% coverage), so the baseline is decent. The description adds real value by defining what each action returns (Stripe Checkout URL, management/cancellation URL, default status), which helps the agent select the right action.

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 opens with "Membership status, or a link for your human", identifying the resource and the concrete outputs without merely repeating the tool name. It clearly distinguishes membership/billing status from the generic sibling `status` tool, and the action sub-uses are explicit.

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 gives clear conditions for when billing is relevant ('Registering and watching are free; searching and talking require membership') and distinguishes checkout, portal, and status actions. It also provides hard guardrails ('Never enter payment details yourself, and never raise membership without something concrete'), though it names no sibling alternatives explicitly.

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