Get the latest foreign-exchange rates for a base currency (default USD), optionally limited to specific target currencies. Source: European Central Bank reference rates.
| Name | Required | Description | Default |
|---|---|---|---|
| base | No | 3-letter base currency, e.g. USD, EUR (default USD) | |
| symbols | No | Optional comma-separated targets, e.g. EUR,GBP,JPY |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Description indicates a read operation ('Get the latest') and states the data source, but with no annotations, it could benefit from mentioning update frequency, caching, or any side effects. It is adequate but not comprehensive.
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, front-loaded sentences with no extraneous information. Every word adds value.
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 simple rate retrieval with no output schema, the description covers the core functionality (latest rates, base, targets, source). A minor addition about return format would improve completeness, but it is largely sufficient.
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 coverage is 100%, so the description does not need to add much; it confirms defaults and optionality, but adds no new semantic detail beyond what the schema already provides.
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?
Description clearly states the tool retrieves latest foreign-exchange rates for a base currency with optional target currencies, and explicitly names the data source (European Central Bank). This distinguishes it from sibling tools like fx_historical or fx_convert.
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?
No guidance on when to use this tool versus alternatives (e.g., fx_historical for past rates, fx_convert for conversions). Users must infer from the tool name and description alone.
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 operation: one-off conversion, currency listing, latest rates, historical rates, and time-series analysis. There is no meaningful overlap between any pair.
All tools share the fx_ prefix, but naming style is inconsistent: fx_convert is a verb, while fx_currencies, fx_rates, fx_historical, and fx_timeseries are nouns/adjectives. Consistent verb_noun names such as list_currencies or get_rates would improve predictability.
Five tools is well-scoped for an FX reference-rate server: one converter, one metadata endpoint, and three rate-lookup variants. Each tool serves a distinct, useful purpose with no bloat.
The surface covers the core FX use cases: listing supported currencies, latest rates, historical rates, time series, and amount conversion. No obvious missing operation is needed for the stated domain.