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

The readOnlyHint=true annotation already tells the agent this is a safe, non-mutating read, so the description need not restate that. It adds nothing further, though: no pagination, sort order, or scope-limits context. With annotations covering the safety profile, this is an adequate but thin 3.

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?

One front-loaded sentence with zero filler; the resource and scope examples are stated immediately. It is efficiently sized for a trivial single-optional-param read tool, though it offers no structure beyond the single clause.

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?

For a read-only tool with one optional enum parameter, no output schema, and no nesting, the description covers purpose and scope adequately. Nothing an agent needs to call it correctly is missing, though the absence of any filtering/return context keeps it short of excellent.

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%, and the single status enum param is fully documented in the schema ('Filter by status (omit for all statuses)'). The description adds no parameter detail beyond it, so the baseline 3 for high coverage applies.

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 clear verb (Get) and resource (recurring payments) and disambiguates the resource by enumerating what counts as recurring payments (subscriptions, bills, upcoming charges). It does not explicitly contrast with siblings, but the resource is distinct enough from the other list/summary tools to be selectable.

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 parenthetical scope note implies when this tool applies (recurring rather than one-off transactions), but there is no explicit when-to-use vs when-not, no mention of alternatives, and no prerequisites. Usage is inferable rather than stated.

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