get_subscription

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

With no annotations, the description carries the full behavioral disclosure burden and does so thoroughly. It explains the exact response shape, the meaning of ends_at, the edge case for free accounts, and explicitly states that the tool takes no arguments.

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 compact and front-loaded with the core purpose. Every sentence adds meaningful information: scope differentiation, response schema, field semantics, and an edge-case clarification. No redundant or filler content is present.

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 (zero parameters, no output schema, no annotations), the description is remarkably complete. It provides the full response structure, explains the tricky field semantics, and clarifies ambiguous status values, so an agent can invoke it and interpret results 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?

There are zero parameters and the schema is empty, so the description only needs to confirm that no arguments are required, which it does. The baseline for zero-parameter tools is 4, and the description fully covers the only relevant semantic point.

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 identifies the tool as returning the account's plan state, explicitly distinguishing it from a site's state. This differentiates it from the sibling tools, which are site- or stats-oriented. The response format and status meanings 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?

The description makes it clear that this tool is for retrieving account-level subscription/plan information, not site-specific data. It does not explicitly name alternatives or exclusion conditions, but for a parameterless getter with no sibling providing subscription data, the usage context is sufficiently clear.

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