get_subscription

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

With no annotations provided, the description carries full burden. It indicates a read-only operation ('View') and specifies the scope of data returned, but doesn't disclose behavioral traits like authentication requirements, rate limits, error conditions, or whether it requires an active subscription. It adds useful context about what data is included but lacks operational details.

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, well-structured sentence that efficiently conveys the tool's purpose and key data points without unnecessary words. It's front-loaded with the core action and resource, and every element (meals per week, servings, price, next delivery) adds specific value.

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 (0 parameters, no annotations, no output schema), the description adequately covers the basic purpose and data scope. However, for a tool that likely requires authentication and returns structured subscription data, the lack of output format details or behavioral context leaves some gaps in completeness.

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 tool has 0 parameters with 100% schema description coverage, so the schema already fully documents the lack of inputs. The description doesn't need to compensate for parameter gaps, and it appropriately doesn't mention parameters since none exist. A baseline of 4 is appropriate for zero-parameter tools.

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 verb ('View') and specific resource ('your current HelloFresh subscription plan details'), listing concrete attributes like meals per week, servings, price, and next delivery. It distinguishes from siblings by focusing on subscription details rather than delivery schedules, menus, orders, or modifications.

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 implies usage context by specifying 'current' subscription details, suggesting it's for checking active plan information. However, it doesn't explicitly state when to use this versus alternatives like 'modify_subscription' or 'get_delivery_schedule', nor does it provide exclusion criteria or prerequisites.

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