> For the complete documentation index, see [llms.txt](https://docs.coherent.global/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.coherent.global/assistant/custom-functions.md).

# Custom Functions

- [SPARK\_XCALL](https://docs.coherent.global/assistant/custom-functions/spark_xcall.md): Xcall is designed for users to call other Spark service APIs inside one service
- [REGEXMATCH](https://docs.coherent.global/assistant/custom-functions/regexmatch.md): Returns the result of matched results given a regular expression and string.
- [REGEXSEARCH](https://docs.coherent.global/assistant/custom-functions/regexsearch.md): Returns the location of matched results given a regular expression and string.
- [REGEXTEST](https://docs.coherent.global/assistant/custom-functions/regextest.md): Returns TRUE or FALSE depending on if a regular expression matches a given string.
- [Xcall legacy functions](https://docs.coherent.global/assistant/custom-functions/xcall-legacy-functions.md)
- [CALLAPI](https://docs.coherent.global/assistant/custom-functions/xcall-legacy-functions/callapi.md): This legacy function allows the user to call Spark service API through Coherent Assistant.
- [FILTERJSON](https://docs.coherent.global/assistant/custom-functions/xcall-legacy-functions/filterjson.md): To make it easier to extract data from the Xcall response JSON, you can use the user-defined function Spark\_FilterJSON. This function also works for parsing any other JSON string.
- [GETOUTPUT](https://docs.coherent.global/assistant/custom-functions/xcall-legacy-functions/getoutput.md): Get specific output from CALLAPI block.
- [JSONTOXML](https://docs.coherent.global/assistant/custom-functions/xcall-legacy-functions/jsontoxml.md): Converts an valid JSON string into XML and returns it as string.
- [SETINPUT](https://docs.coherent.global/assistant/custom-functions/xcall-legacy-functions/setinput.md): Returns the absolute address of entered range or named item.
- [UDFCALLAPI](https://docs.coherent.global/assistant/custom-functions/xcall-legacy-functions/udfcallapi.md): This legacy function allows the user to call Spark service API through Coherent Assistant.
- [XMLTOJSON](https://docs.coherent.global/assistant/custom-functions/xcall-legacy-functions/xmltojson.md): Converts an valid XML string into JSON and returns it as string.


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