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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safe read-only nature is covered. The description adds useful behavioral context by limiting reads to requests 'owned by or explicitly addressed to' the participant, which is an authorization constraint beyond the annotations. It does not disclose not-found behavior, error responses, or whether unowned requests are hidden vs. rejected.

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 front-loaded sentence with no filler or redundant phrasing. Every part, especially the ownership/addressee qualifier, contributes to correct tool selection.

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 one-parameter read-only lookup, the description plus annotations supply the core information needed to select and invoke it: read semantics, authorization scope, and the required ID. It leaves the distinction from get_payment and response/failure behavior implicit, but these are secondary for a simple get-by-ID 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?

The input schema only documents paymentRequestId as a required string, and the description never mentions this parameter or adds any detail about its format, origin, or relationship to the ownership constraint. With schema_description_coverage at 0%, the description was expected to compensate but does not, though the single parameter's name is self-explanatory.

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 the specific verb 'Read' and identifies the resource 'a payment request,' then adds an ownership/addressee scope that distinguishes it from generic payment reads. It does not explicitly name sibling tools like get_payment, so some differentiation is left to inference.

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 ownership/addressee condition gives clear context for when this tool is appropriate: fetching a payment request the authenticated participant is allowed to read. However, it does not state when to prefer related tools like get_payment, request_payment, or send_payment, nor does it include exclusions or when-not-to-use guidance.

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