On which Windchill version do you work?
When I don't find standard endpoints in the REST Services, I write them myself.
Since Windchill 11.1 I use Spring to create them.
For that you need an entry in codebase/WEB-INF/web.xml like:
<servlet>
<servlet-name>ConnectorName</servlet-name>
<servlet-class>
org.springframework.web.servlet.DispatcherServlet
</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>ConnectorName</servlet-name>
<url-pattern>/servlet/connector/*</url-pattern>
</servlet-mapping>
In the same folder you need a file named like the Servletname-servlet like ConnectorName-servlet.xml with following content:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:aop = "http://www.springframework.org/schema/aop"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd ">
<context:component-scan base-package="packagename" />
<mvc:annotation-driven />
After this you can create a Spring RestController Class in the package defined above in component-scan.