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

Annotations already declare readOnlyHint=true, so safety is covered. The description goes beyond that by enumerating the concrete fields returned (amount, method, reason, received time, customer, gateway transaction id), which is genuinely useful since there is no output schema. It stops short of noting error behavior for an unknown id.

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 listing the payload, followed by a short endpoint reference. No filler, no redundancy.

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 single-record read tool with readOnlyHint and no output schema, the description supplies the return fields an agent needs to decide whether to call it. Only the failure mode for a nonexistent id is left unaddressed.

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?

There is a single parameter with 100% schema description coverage ('The payment id.'), so the schema already carries the semantics. The description adds nothing about id format or provenance, 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?

The description states a specific verb and resource ('Get one payment') and enumerates the fields returned, so the agent knows exactly what it retrieves. The word 'one' implicitly separates it from the sibling list tools (bookeo_list_payments, bookeo_list_booking_payments), though that contrast is never made explicit.

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: retrieving a single payment by id suggests you already know the id. The description never states when to prefer this over bookeo_list_payments or bookeo_list_booking_payments, nor any precondition for having a valid id.

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