AI-generated currency code often skips rate freshness checks

Exchangeratesapi says its currency responses include timestamps so developers can block stale rates before they are used. The issue matters because AI-written converter code can quietly fall back to old data unless freshness checks are built in.

Why it matters: - AI-generated currency conversion code can return a believable number even when the underlying exchange rate is stale. - That creates a quiet failure mode for checkout flows, reports and other systems that depend on current pricing. - Exchangeratesapi’s timestamped responses are meant to help code reject outdated rates before they affect a transaction.

What happened: - A typical AI-built currency converter calls an exchange rate service, reads the rates and returns a converted value. - The response fields that show how old the rate is are often left unused. - The problem can surface when a cache never expires, a request fails and the code falls back to a stored rate, or a refresh job stops running. - APILayer said an AI coding assistant will write the freshness check when the prompt includes a specific instruction in the project’s instructions file. - The instruction is: “Every exchange rate comes from Exchangeratesapi at runtime. Check the response's timestamp against a maximum age before using a rate, and throw an error when the rate is too old or the request fails.”

The details: - Every Exchangeratesapi response includes the date the rates were collected and a Unix timestamp. - Checking freshness takes one comparison: subtract the timestamp from the current time. - The code should refuse to price anything if the rate is older than the allowed limit or if the request fails. - The acceptable age depends on the use case and the plan. - Exchangeratesapi update intervals vary by plan, including daily, hourly, every 10 minutes and every 60 seconds. - The freshness limit should be set above the plan’s update interval so the check does not fail just before the next update. - Exchangeratesapi covers more than 170 world currencies. - The service draws on more than 15 exchange rate sources. - The API keeps historical records back to 1999. - APILayer said Exchangeratesapi can be used alongside IPstack, which converts a visitor’s IP address into geolocation and a local currency code. - IPstack also offers a Model Context Protocol server for AI assistants and agents, with more MCP servers across the APILayer suite planned. - Developers can test Exchangeratesapi on the free plan at the service website.

Between the lines: - The release is less about exchange rates themselves and more about making AI-generated code safer around data freshness. - Timestamp checks are a small implementation detail, but they reduce the risk of silent pricing errors that can be hard to spot in production. - The emphasis on prompt instructions suggests APILayer wants developers to treat freshness validation as a default coding pattern, not an optional extra.

What's next: - Developers using Exchangeratesapi can add timestamp validation to their prompts, templates or project instructions before deploying currency logic. - APILayer is expanding MCP support across its API suite, which could make its services easier for AI tools and agents to call directly. - The company is steering users toward the free plan for testing before production use.

The bottom line: - A currency rate is only useful if code knows how fresh it is, and Exchangeratesapi is pushing AI-generated applications to check that before they convert anything.