veil_x402_payer_balancesCheck Base USDC balances for deterministic x402 payer EOAs associated with a managed Veil key. Optionally filter to non-zero balances and discover additional payer accounts.
Inspect Base USDC balances held by deterministic x402 payer EOAs for the managed Veil key.
| Name | Required | Description | Default |
|---|---|---|---|
| count | No | ||
| discover | No | ||
| startIndex | No | ||
| nonZeroOnly | No |
Changes observed during successful MCP inspections.
v0.4.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden. 'Inspect' implies a read-only operation, but the description does not explicitly state that it is non-destructive, what permissions or key state are required, or whether there are rate limits or caching considerations.
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?
A single front-loaded sentence with no wasted words. The core purpose and scope are immediately clear, making efficient use of the space.
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 tool with four undocumented optional parameters, no annotations, and no output schema, the description is too sparse. It provides purpose but omits any explanation of the parameters, usage context, or behavioral constraints an agent needs to call it correctly.
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 schema has 4 parameters with 0% description coverage, and the description mentions none of them (count, discover, startIndex, nonZeroOnly). It therefore adds no meaning beyond the bare schema and fails to compensate for the complete lack of parameter documentation.
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 uses a specific verb ('Inspect') and a precise resource ('Base USDC balances held by deterministic x402 payer EOAs for the managed Veil key'). It clearly identifies the domain, though it does not explicitly differentiate this tool from close siblings like veil_x402_receipts or agent_eoa_get_balance.
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 states what the tool does but gives no guidance on when to use it versus alternatives such as veil_get_balances or agent_eoa_get_balance. There are no prerequisites, exclusions, or conditions mentioned.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.