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

Annotations mark destructiveHint: true, but the description adds critical behavioral context: the tool is two-step, returns a preview needing explicit confirmation, can return a Swop-app approval link instead of executing when over cap or confirm-only, and does not execute on the first call. This goes well beyond the annotations and materially changes how an agent should call it.

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: the first states the action and recipient, the second gives the precise two-step procedure, and the third adds a necessary safety warning. Every sentence contributes essential information with no filler.

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 multi-step destructive tool with no output schema, the description sufficiently explains the full call lifecycle: preview, user confirmation, final execution, and edge cases such as over-cap and confirm-only settings. Nothing needed for correct invocation is missing.

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?

Input schema already covers all parameters with descriptions, so the baseline is 3. The description adds value by explaining how confirm and previewId relate to the two-step flow, clarifying that amountUsd is sent as USDC, and noting caps behavior. This enriches parameter understanding beyond the schema.

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: 'Send USDC (on Base) from the linked Swop wallet' to 'a swop.id handle or 0x address.' This clearly identifies the operation and its scope, and it is distinct from sibling tools like swop_get_swap_quote or swop_pay_x402_link.

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 provides explicit when and how instructions: call without confirm first, show the preview to the user, get explicit yes, then call again with previewId and confirm: true. It also states a firm negative rule: 'Never call with confirm before the user has seen the preview.' This is strong operational guidance.

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