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

Annotations already mark destructiveHint=true and readOnlyHint=false, and the description goes well beyond that by explaining token validity, placeholder-token invalidity, the confirmation_required response, the role of confirmWrite, the meaning of preflight, and the scoping of counterparty confirmation. This is rich behavioral context that annotations alone would not provide.

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 front-loaded with its core purpose and then builds into the confirmation workflow. It is longer than average, but nearly every sentence carries operative information about token handling or confirmation semantics. A small amount of redundancy exists between 'routeToken does not bypass' and 'passing preflight is not confirmation.'

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 the tool's complexity and lack of an output schema, the description covers the most critical operational facts: required routeToken, confirmation_required return behavior, confirmWrite semantics, and counterparty confirmation. It does not fully describe return payloads after successful confirmation or map all mode-specific parameters, so it is not perfect, but it is strong enough for an agent to invoke the tool safely.

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 coverage is 68%, and the description adds meaningful semantics for the most safety-critical parameters: routeToken, confirmWrite, and confirmCounterpartyExplicit. It explains what happens when confirmWrite is absent, and that a routeToken does not bypass preview. Some parameters like acCode, accountCode, and supplierId are not mapped in the description, but their schema descriptions cover the basic intent.

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 a specific verb and resource: 'Creates a bank payment' and further clarifies two distinct modes: supplier or analysed-account. This cleanly separates the tool from sibling create-payment tools like brc_create_cash_payment and brc_create_purchase.

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?

It clearly states the prerequisite routeToken requirement and the confirmation flow. However, it does not explicitly name alternatives (e.g., 'use brc_create_cash_payment for cash payments'), so the when-not-to-use guidance is mostly implied by the word 'bank payment.'

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