joltsms_list_payment_methods

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

With no annotations, the description carries the burden and does real work: it enumerates the return fields and gives an explicit security guarantee ('Never returns full card numbers or CVC'), which an agent cannot derive from the schema. It stops short of stating permission requirements or pagination behavior.

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?

Two tight sentences, zero filler, and the purpose plus the key privacy constraint are front-loaded before the return-field list.

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?

There is no output schema, so the description correctly compensates by listing the returned fields and the payment_method_id. It omits any note on ordering, pagination continuation, or auth context, which are minor but real gaps for a paged list tool.

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% – limit and cursor are fully documented in the schema with ranges, defaults, and meaning. The description adds no syntax or semantics beyond that, so the baseline 3 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 specific verb and resource ('List masked saved cards') and adds the intent behind the call ('so the user can choose which card funds a number rental'). This is unmistakably distinct from the number, message, and OTP 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?

The purpose clause implies the usage moment (choosing a funding card for a number rental), but it never names a workflow sibling such as joltsms_provision_number or states a prerequisite. Usage is inferable, not explicit.

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