We offer this new dictum: Context is king when it comes to transaction data — and one new startup is staking its future on that.

Today, it is becoming standard in banking for APIs (application programming interfaces) to provide rich contextual data in order to deliver value to developers and marketers. No longer is it acceptable to pass along the garbled string of numbers generated by a merchant’s payment processor. Value has to be added to transaction data by scrubbing it, which makes it human-readable, and by providing additional context wherever possible.

One company offering this enhanced data through its API is San Francisco-based Plaid, which makes transaction data richer and easier to interpret. For example, if a customer ate at a Mexican restaurant in New York on Tuesday, Plaid would offer the restaurant’s name, type of cuisine, location, website and phone number. Over time, a consumer’s restaurant habits would be very clear to those with access to Plaid’s API.

Plaid received $2.8 million in seed funding in August 2013 and has since launched support for JPMorgan Chase, Bank of America, Citibank, Wells Fargo, US Bank, American Express USAA — not a bad group. Plaid’s enhanced data is being used by accountants, tax preparers, and expense managers, among others, in an ongoing beta.

Data cleansing is a major task for companies in the personal financial management space that are trying to make transactions human readable. Yodlee, Intuit and MoneyDesktop devote a great deal of effort to this task. Wouldn’t it be nice if the data arrived clean and human-readable in the first place?

Another company offering enhanced or contextual data is Vancouver-based Nerture, which partners with merchants to offer SKU-level data on transactions.

With souped-up transaction data passing through APIs to developers of innovative service, some of the promise of Big Data can be realized.