convert_manyConvert a single amount from one currency into multiple target currencies using ECB rates, with each result rounded to its currency's minor units.
One amount, one source currency, many targets, all off the same ECB rate date. Each result is rounded to that target's own minor units.
| Name | Required | Description | Default |
|---|---|---|---|
| to | Yes | Target currencies | |
| from | Yes | ||
| amount | Yes |
Changes observed during successful MCP inspections.
v0.20.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the behavioral burden. It adds meaningful behavioral details beyond the schema: all conversions share the same ECB rate date, and each result is rounded to its target currency's minor units. It does not describe the response shape, but the described behavior is clear and non-contradictory.
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 concise sentences deliver the core behavior without wasted words. The key constraint (one source, many targets, same rate date) is front-loaded, and the rounding detail adds value without bloating the description.
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?
The description covers input semantics and key behavior, but there is no output schema and no explanation of what the result format looks like. An agent can invoke the tool reasonably well, but it cannot predict whether the response is an array, a map keyed by currency, or something else.
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 only 33%, so the description must compensate. It maps 'amount' to the single input amount, 'from' to the source currency, and 'to' to the many target currencies. This gives the agent the parameter roles even though the schema only documents 'to' with a brief 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?
The description states a specific verb ('Convert') with a precise resource scope: one amount, one source currency, many target currencies, all using the same ECB rate date. The 'many targets' qualifier clearly distinguishes this tool from the sibling 'convert' and other rate-related tools.
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 clearly implies the intended use case: converting one amount into multiple currencies at once. It does not explicitly name alternatives or state when not to use the tool, but the 'one source, many targets' framing gives an agent enough context to select it over the singular 'convert' sibling.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.