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

The description implies a read operation via 'Returns', but with empty annotations it does not explicitly state safety guarantees, prerequisites, or side effects. It also includes a confusing @return note about customer id that may contradict the stated purpose, though not egregiously.

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 main description is compact and front-loaded, but the @return annotation appears potentially inaccurate or confusing, referencing customer id rather than subscription status. This slightly undermines the conciseness and clarity of an otherwise efficient description.

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 one-parameter read tool, the description is largely sufficient: it states the purpose and parameter semantics, and an output schema exists. However, it lacks mention of prerequisites or edge cases, and the return note adds ambiguity, keeping it from being fully complete.

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 description explains customer_id as 'The customer's database id', adding meaning beyond the bare integer type. Given 0% schema description coverage, this is valuable, though it does not elaborate on how to obtain the id or any constraints.

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 returns the customer's current subscription status, specifying expiry_date, which distinguishes it from related tools like validation or logging. The verb 'Returns' and the specific resource make the purpose 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?

There is no guidance on when to use this tool versus alternatives such as paywall__customer_validate_subscription or paywall__customer_log_subscription. No context or exclusions are provided, leaving the agent to infer usage solely from the tool name and description.

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