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

Annotations already declare readOnlyHint=true and the title restates the operation, so the safety profile is covered. The description adds that results are scoped to a single order, but says nothing about whether an empty list is returned for an order with no subscriptions or about pagination behavior (though the schema documents page/limit/next_page).

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?

A single front-loaded sentence with zero filler. It is arguably too terse for a 9-parameter filtered-list tool, but as a matter of conciseness and structure it is well-formed.

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?

Adequate minimum for a read-only list tool whose schema fully documents all nine parameters. However it leaves the sibling relationship to recurpay_list_subscriptions unstated and gives no hint about the shape or typical contents of the returned subscription list, which has no output schema.

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?

Schema description coverage is 100%, including the order_id provenance note ('from recurpay_list_orders') and all filter/sort/pagination params, so the schema carries the full parameter burden. The description adds only the implicit confirmation that order_id is the scoping key — baseline 3.

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?

States a specific verb (list) and resource (subscriptions) plus a clear scope: subscriptions belonging to one order. This implicitly distinguishes it from recurpay_list_subscriptions, but the description never names or contrasts that sibling, so an agent must infer the difference.

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?

Usage is only implied by the word 'order' — an agent can infer you call this when you have an order_id and want its subscriptions. There is no explicit when-to-use, when-not-to-use, or pointer to recurpay_list_subscriptions for tenant-wide listings.

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