This module may be appended to a template to check for uses of unknown parameters.

{{#invoke:check for unknown parameters|check
|unknown=[[Category:Some tracking category]]
|arg1|arg2|...|argN}}

or to sort the entries in the tracking category by parameter

{{#invoke:check for unknown parameters|check
|unknown=[[Category:Some tracking category|_VALUE_]]
|arg1|arg2|...|argN}}

or for an explicit red error message

{{#invoke:check for unknown parameters|check
|unknown=<span class=error>Sorry, I don't recognize _VALUE_</span>
|arg1|arg2|...|argN}}

or to use hidden error messages which can be viewed in the HTML source

{{#invoke:check for unknown parameters|check
|unknown=<span style="display:none">HIDDEN ERROR: Usage of "_VALUE_" is not recognized</span>
|arg1|arg2|...|argN}}

Here, arg1, arg2, ..., argN, are the known parameters. Any parameter which is used, but not on this list, will cause the module to return whatever is passed with the unknown parameter. The _VALUE_ keyword, if used, will be changed to the name of the parameter. This is useful for either sorting the entries in a tracking category, or for provide more explicit information.

By default, the module makes no distinction between a defined-but-blank parameter and a non-blank parameter. To only track non-blank parameters use |ignoreblank=1.

{{Infobox
| above = {{{name|}}}

| label1 = Height
| data1 = {{{height|}}}

| label2 = Weight
| data2 = {{{weight|}}}

| label3 = Website
| data3 = {{{website|}}}
}}<!-- 
  end infobox, start tracking
-->{{#invoke:Check for unknown parameters|check
| unknown = [[Category:Some tracking category|_VALUE_]]
| name
| height | weight
| website
}}