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

With no annotations provided, the description carries the full burden of behavioral disclosure. It reveals only that authentication is required and that the result is scoped to the authenticated user. It does not disclose return format, pagination behavior, defaults, error conditions, or whether the operation is read-only, which is especially important given the absence of an output schema.

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 a single efficient sentence with no filler, and the primary action is front-loaded. It is slightly unstructured (parameters are tacked on as a clause), but overall it is appropriately short and scannable for an agent.

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 three parameters, no annotations, and no output schema, the description is not complete enough. It fails to explain the return shape, pagination semantics, sessionKey usage rules already implied by the schema, or typical use cases. An agent would likely need to guess about defaults and response structure.

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 only 33%, so the description should clarify the undocumented parameters. It mentions 'page' and 'size' are optional integers, but the schema already indicates their types and optionality. It does not explain what page/size control, valid ranges, defaults, or how sessionKey relates to authentication, leaving meaningful gaps.

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 states a clear verb ('Get') and resource ('payment transaction history') scoped to the authenticated user. It identifies the tool as a history/listing operation, which is distinct from related invoice or balance tools, though it does not explicitly name a sibling to differentiate against.

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 notes that authentication is required and that page/size are optional, giving some operational context. However, it does not say when to prefer this tool over alternatives like getInvoiceDetails, getRecentActivity, or getAccountBalance, nor does it describe any exclusions or limitations.

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