diff --git a/OpenTools_Ordernumber_Framework_API.txt b/OpenTools_Ordernumber_Framework_API.txt
new file mode 100644
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+++ b/OpenTools_Ordernumber_Framework_API.txt
@@ -0,0 +1,59 @@
+OpenTools Ordernumber Library
+=============================
+
+API functions:
+~~~~~~~~~~~~~~
+  -) registerCallback($callback, $func)
+  -) createNumber($fmt, $type, $order, $customvars, $ctrsettings)
+  -) createJSSetup()
+  -) custom_variables_create_table($id, $variables)
+  -) counter_modification_create_table($type, $counters)
+  -) setFlag($flag, $value)
+  -) unsetFlag($flag)
+  -) getFlag($flag, $default)
+
+Flags:
+~~~~~~
+  -) 'extract-counter-settings': Allow the counter to include padding, increment, reset or not; e.g. [#####:100/15]
+
+E-commerce specific functions (to be overridden in child classes!):
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+  -) __($string)             // or use the translate callback for your own function!
+  -) urlPath($type, $filename)  // If not overridden, callback is used
+  -) getAllCounters($type)
+  -) getCounter($type, $countername, $default)
+  -) setCounter($type, $countername, $value)
+  -) addCustomJS(&$json)
+  -) appendJS()    // Add e-commerce-specific JS code
+
+
+Callback functions:
+~~~~~~~~~~~~~~~~~~~
+  -) translate($message)
+  -) urlPath($type, $filename)
+  -) getCounter($type, $countername, $default)
+  -) setCounter($type, $countername, $value)
+  -) setupDateTimeReplacements(&$reps, $details, $nrtype);
+  -) setupStoreReplacements(&$reps, $details, $nrtype);
+  -) setupOrderReplacements(&$reps, $details, $nrtype);
+  -) setupUserReplacements(&$reps, $details, $nrtype);
+  -) setupShippingReplacements(&$reps, $details, $nrtype);
+  -) setupThirdPartyReplacements(&$reps, $details, $nrtype);
+
+
+E-commerce specific members of the helper class (to be set in child classes!):
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+  -) $_styles[...]: CSS styles for the HTML tables. Possible keys:
+        o) 'counter-table-class'
+	o) 'counter-table-style'
+	o) 'variable-table-class'
+	o) 'variable-table-style'
+  -) $ajax_url: The URL for the AJAX calls
+
+
+AJAX modifications (JS):
+~~~~~~~~~~~~~~~~~~~~~~~~
+  -) ajax_ordernumber.updateMessages: Show messages generated during AJAX calls
+  -) ajax_ordernumber.parseAjaxResponse: Parse the AJAX return value to JSON; only if the default does not work
+  -) ajax_ordernumber.modifyAjaxArgs: Modify the arguments sent in the AJAX call (e.g. if text format instead of json is requested, etc)
+