Look up current foreign exchange rates between major world currencies. Returns exchange rate, bid/ask spread, and last update timestamp. Use for travel planning, international business transactions, or forex trading decisions.
| Name | Required | Description | Default |
|---|---|---|---|
| base | No | Base currency code for rate calculation (e.g. 'USD', 'EUR', 'GBP', 'JPY') | USD |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds context about return data (bid/ask spread, timestamp) and the 'current' nature of rates, but does not mention data source, refresh rate, or limitations. This matches the calibration baseline of 3.
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, with the first sentence front-loaded with the purpose and the second adding return details and use cases. Every word earns its place, making it highly concise and well-structured.
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 tool with one optional parameter and no output schema, the description is complete: it states what it does, what it returns (key fields), and when to use it. No critical information is missing for a read-only lookup tool.
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 100% (the only parameter 'base' is fully described). The tool description does not add any additional parameter meaning beyond the schema, so the baseline of 3 is appropriate.
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's function with a specific verb ('Look up') and resource ('current foreign exchange rates between major world currencies'). It also lists the return fields, distinguishing it from sibling tools focused on crypto and stocks.
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 explicit use cases (travel planning, international business, forex trading) which imply when to use the tool. However, it does not explicitly name alternatives or state when not to use it, so it falls short of a 5.
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.
Most tools have clearly distinct purposes: crypto prices, exchange rates, stock data, stock screening, and crypto portfolio tracking. However, get_crypto_prices and track_crypto_portfolio both return crypto price data, and get_stock_data and screen_stocks are related but distinct in action.
All tool names follow a consistent verb_noun pattern in snake_case (get_, screen_, track_). The 'get_' prefix is used for three tools, with 'screen_' and 'track_' as appropriate action verbs. No mixed conventions.
Five tools is well-scoped for a finance server covering cryptocurrencies, exchange rates, and stocks. Each tool earns its place, covering core data retrieval and screening functions without unnecessary bloat.
The tool set covers key finance use cases: price lookups, screening, and portfolio tracking. Minor gaps exist, such as no historical price data or stock portfolio tracking, but the primary domain is well-served.