Retrieve account balances as of a specified date using base currency, excluding FX postings without a base amount. Ideal for generating trial balance reports.
Balances by live account through an inclusive posting entry date. Uses base currency and rejects FX postings without a base amount.
| Name | Required | Description | Default |
|---|---|---|---|
| asOf | Yes | ||
| accountIds | No | ||
| includeZero | No |
Changes observed during successful MCP inspections.
v0.2.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already establish readOnly, idempotent, non-destructive behavior. The description adds valuable behavioral context beyond that: the date filter is inclusive, the tool operates in base currency, and FX postings without a base amount are rejected. No contradiction with annotations exists.
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?
Two short sentences with no filler. The core action is front-loaded, and the second sentence adds distinct behavioral detail about currency handling and FX rejection. Every phrase earns its place.
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 read-only, three-parameter query, the description covers the essential behavior: inclusive as-of date, live-account grouping, base-currency handling, and FX rejection. It does not describe the output shape, but no output schema exists and the tool name plus 'balances' makes the return concept clear. Minor gaps around optional filters are acceptable.
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 0%, so the description must compensate. It clarifies that asOf is an inclusive posting entry date and that balances are per live account, which partially maps to accountIds, but it does not explain includeZero or the exact semantics of accountIds filtering. Compensation is incomplete.
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?
States a specific verb ('Balances') and resource ('by live account') with a temporal scope ('through an inclusive posting entry date'), so the core action is clear. It does not explicitly contrast itself with siblings like billy_profit_loss or billy_period_expenses, so it misses full differentiation.
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 implies when to use the tool—when you need account balances through a date—but gives no explicit when-to-use guidance and names no alternatives. With many financial sibling tools present, an agent gets little help choosing between this and billy_profit_loss or billy_journal.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.