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

Annotations already declare destructiveHint=true and readOnly=false. The description adds meaningful context beyond annotations: 'DPX runs the full oracle gate → compliance screen → settlement flow' and 'Returns a receipt,' clarifying that this triggers a multi-step pipeline, not just a simple payment call. No contradiction with annotations.

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?

Three sentences with a front-loaded purpose and examples, followed by usage alternatives and execution flow. Efficient and well-structured, though there is slight redundancy between 'Call this instead of typing credentials into a UI' and 'Use whenever computer use encounters a payment...'

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, the rich input/output schemas, and a large sibling set, the description is quite complete: it covers the execution pipeline, return receipt, and the key distinction from manual credential entry. A short note on prerequisites or authorization would elevate it, but the current coverage is solid.

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%, so the baseline applies. The main description mentions 'provide the amount and recipient' and 'Describe what you see on screen,' but these add little beyond the already-rich parameter descriptions in the schema. The useful alternative-tool hint for recipient_address is in the schema, not the main description.

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?

Specific verb 'Complete a payment' with clear context: identified on screen by computer use, with concrete examples (checkout form, wire transfer UI, invoice approval, vendor portal). Distinguishes from siblings by 'Call this instead of typing credentials into a UI,' making the tool's unique role 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?

Explicit when-to-use guidance: 'Use whenever computer use encounters a payment that would otherwise require human re-entry or approval.' Also provides an alternative: 'If only bank/email visible, use settlement.nl instead' (in schema), and tells agents to call this instead of typing credentials into a UI.

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