Convert an amount between major currencies (USD, EUR, GBP, JPY, CAD, AUD, CHF, CNY, INR) with Decimal precision. Static offline table on the free tier; live/historical ECB rates (date/live=true) require a paid plan.
| Name | Required | Description | Default |
|---|---|---|---|
| date | No | ||
| live | No | ||
| amount | Yes | ||
| to_currency | Yes | ||
| from_currency | Yes |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. It reveals Decimal precision, the static offline table on the free tier, and the paid requirement for live/historical rates. This adds meaningful context about data freshness and accuracy, though it does not cover possible errors or edge cases.
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 two sentences, front-loaded with the primary action, and every phrase adds value. It covers scope, precision, and usage constraints without unnecessary fluff.
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 five parameters, no output schema, and no annotations, the description provides a high-level overview but leaves ambiguity about how date and live combine, what the returned result looks like, and any error conditions. It is adequate for a simple conversion tool but not fully complete.
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 lists supported currencies, which informs value choices for from_currency and to_currency, and hints at the date/live interaction. However, it does not explicitly explain the formats or semantics of amount, date, or live, leaving some guesswork for the agent.
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 clearly states the tool converts amounts between major currencies, listing specific currency codes and noting Decimal precision. This distinguishes it from sibling financial calculation tools, which cover unrelated operations like batch calculations and net present value.
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 clear context about when to use the free tier versus the paid plan, mentioning static offline tables for basic conversions and live/historical ECB rates requiring a paid plan. While it doesn't explicitly name alternatives, the distinct scope of the tool makes usage straightforward, and the tier distinction guides decisions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool targets a distinct calculation domain: business days, SaaS metrics, compound growth, FX, depreciation, IRR, NPV, loans, and batch execution. The only closely related pair (IRR and NPV) is clearly differentiated by descriptions.
Most tools use snake_case, but the pattern is mixed: calculate_metric and list_metrics are verb-first, currency_convert is verb-last, batch_calculate starts with a modifier, and the rest are noun phrases like loan_amortization and net_present_value. This inconsistency could cause minor confusion but remains readable.
11 tools is well within the typical range for a specialized calculator server. Each tool covers a distinct area, and the auxiliary tools (list_metrics, batch_calculate, health_check) support the core set without bloat.
The server covers a broad swath of business/finance calculations: time-value-of-money (NPV, IRR, compound growth), loans, depreciation, currency, business days, and SaaS metrics. Minor gaps exist (e.g., no general unit conversion or statistical functions), but for the stated purpose the surface is complete.