"code": "LeadingOrTrailingException",
	"target": "Unknown",
	"details": [
			"code": "LeadingOrTrailingException",
			"number": 175,
			"message": "Error parsing $filter.",
			"description": "The $filter value '-0-' had an invalid leading or trailing conjunction.  Please check your query and try again.",
			"faultCode": "Client",
			"helpLink": "http://developer.avalara.com/avatax/errors/LeadingOrTrailingException",
			"severity": "Error"

This indicates that your $filter query parameter was not correctly formatted. This error occurs when you have a conjunction between two clauses, but one of the two clauses is missing.

Conjunctions are the boolean logic statements AND / OR. When a conjunction appears, there must be a filter clause both before the conjunction and after the conjunction. You will get a LeadingOrTrailingException if your conjunction is missing either the leading or trailing filter clause.

Some examples of this error:

  • $filter=id gt 123 and - In this case, the word “AND” appears at the end of the filter, but there is no filter clause after it. This is called a trailing conjunction error.
  • $filter=and id gt 123 - The word “AND” appears as the first word at the beginning of the filter, but there is no filter clause before it. This is called a leading conjunction error.