ls_list_subscription_items

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

Annotations confirm read-only, idempotent, non-destructive. Description adds pagination details and cross-store constraints, going beyond annotations. No contradictions.

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 concise sentences: core function, pagination, cross-store note. No redundant information; each sentence earns its place.

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 5 parameters all documented in schema and no output schema, the description covers pagination and cross-store constraints completely. Annotations provide additional safety assurance.

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?

Although schema describes all 5 parameters, the description explains the significance of subscriptionId and priceId in the cross-store context, adding value beyond schema. No enums or nested objects needed.

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?

Clearly states 'List all subscription items' with optional filters, distinguishing it from other list tools. The verb 'list' and resource 'subscription items' are specific and unambiguous among siblings.

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?

Explicitly mentions pagination and cross-store restrictions: when LEMONSQUEEZY_ALLOWED_STORE_IDS is set, requires at least one filter. Provides actionable guidance on when to use filters and how to handle cross-store API keys.

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