ls_list_subscription_items

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

Annotations already establish read-only, idempotent, non-destructive behavior. The description adds substantial behavioral context beyond that: the paginated response envelope, the authoritative effective_unit_price on embedded price records rather than unit_price, and the API-key-level cross-store boundary. No contradiction with annotations exists.

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 front-loaded with purpose and every section carries useful information, but it is dense and the cross-store sentence is slightly verbose with an awkward 'Even with that set, Pair...' phrase. It earns its length overall, though not with maximum polish.

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 has no output schema, the description fills the gap well by explaining the pagination metadata shape and the meaning of embedded price records. It also covers important cross-store constraints, making the tool callable correctly in both single-store and multi-store environments.

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?

Even though schema coverage is 100%, the description adds critical parameter meaning: include=price's effect, effective_unit_price semantics, and the conditional requirement on subscriptionId/priceId under cross-store configuration. This is exactly the kind of non-obvious semantic guidance agents need.

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 a specific verb and resource: 'List all subscription items' and immediately clarifies the optional filters by subscription or price. This distinguishes it from sibling resources like subscriptions, subscription invoices, and subscription item usage records, even without naming an alternative.

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 gives clear usage context: pagination via meta.page, how to include price records, and the cross-store requirement that subscriptionId or priceId must be supplied when LEMONSQUEEZY_ALLOWED_STORE_IDS is set. It does not explicitly compare against alternative tools, but the guidance is strong enough to select and call confidently.

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