When ADFS 2.0 is used as a service provider (i.e. RP STS) it consumes assertions at URLs like https://sts.contoso.com/adfs/ls/ .
The assertion consumer service URL is specific to the service provider. If ADFS is the service provider then the metadata URLs publish the assertion consumer URLs as follows.
<AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Location="https://sts.contoso.com/adfs/ls/" index="0" isDefault="true" />
<AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Artifact" Location="https://sts.contoso.com/adfs/ls/" index="1" />
<AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Redirect" Location="https://sts.contoso.com/adfs/ls/" index="2" />
And here is some sample assertion consumer service URLs from another test site for comparison. http://www.testshib.org/metadata/testshib-two-metadata.xml
<AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST" Location="https://sp.testshib.org/Shibboleth.sso/SAML2/POST" index="1" isDefault="true" xmlns="urn:oasis:names:tc:SAML:2.0:metadata" />
<AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST-SimpleSign" Location="https://sp.testshib.org/Shibboleth.sso/SAML2/POST-SimpleSign" index="2" xmlns="urn:oasis:names:tc:SAML:2.0:metadata" />
<AssertionConsumerService Binding="urn:oasis:names:tc:SAML:2.0:bindings:HTTP-Artifact" Location="https://sp.testshib.org/Shibboleth.sso/SAML2/Artifact" index="3" xmlns="urn:oasis:names:tc:SAML:2.0:metadata" />
<AssertionConsumerService Binding="urn:oasis:names:tc:SAML:1.0:profiles:browser-post" Location="https://sp.testshib.org/Shibboleth.sso/SAML/POST" index="4" xmlns="urn:oasis:names:tc:SAML:2.0:metadata" />
<AssertionConsumerService Binding="urn:oasis:names:tc:SAML:1.0:profiles:artifact-01" Location="https://sp.testshib.org/Shibboleth.sso/SAML/Artifact" index="5" xmlns="urn:oasis:names:tc:SAML:2.0:metadata" />
<AssertionConsumerService Binding="http://schemas.xmlsoap.org/ws/2003/07/secext" Location="https://sp.testshib.org/Shibboleth.sso/ADFS" index="6" xmlns="urn:oasis:names:tc:SAML:2.0:metadata" />