Following http://docs.opendaylight.org/en/stable-boron/user-guide/bgp-user-guide.html, I configured

1) bgp instance

POST http://localhost:8181/restconf/config/openconfig-network-instance:network-instances/network-instance/global-bgp/openconfig-network-instance:protocols

<protocol xmlns="http://openconfig.net/yang/network-instance">
<name>bgp-example</name>
<identifier xmlns:x="http://openconfig.net/yang/policy-types">x:BGP</identifier>
<bgp xmlns="urn:opendaylight:params:xml:ns:yang:bgp:openconfig-extensions">
<global>
<config>
<router-id>127.0.0.1</router-id>
<as>65000</as>
</config>
</global>
</bgp>
</protocol>

2) remote peer

POST http://localhost:8181/restconf/config/openconfig-network-instance:network-instances/network-instance/global-bgp/openconfig-network-instance:protocols/protocol/openconfig-policy-types:BGP/bgp-example/bgp/neighbors

<neighbor xmlns="urn:opendaylight:params:xml:ns:yang:bgp:openconfig-extensions">
<neighbor-address>127.0.0.2</neighbor-address>
<timers>
<config>
<hold-time>90</hold-time>
<connect-retry>10</connect-retry>
</config>
</timers>
<transport>
<config>
<remote-port>17900</remote-port>
<passive-mode>false</passive-mode>
</config>
</transport>
<config>
<peer-type>INTERNAL</peer-type>
</config>
</neighbor>

3) started remote peer

java -jar ./target/bgp-testtool-0.6.3-Boron-SR3-executable.jar -ra 127.0.0.1:1790 -la 127.0.0.2:17900 -pr 2 -ll DEBUG --active true -as 65000

4) application peer

POST http://localhost:8181/restconf/config/openconfig-network-instance:network-instances/network-instance/global-bgp/openconfig-network-instance:protocols/protocol/openconfig-policy-types:BGP/bgp-example/bgp/neighbors

<neighbor xmlns="urn:opendaylight:params:xml:ns:yang:bgp:openconfig-extensions">
<neighbor-address>10.25.1.10</neighbor-address>
<config>
<peer-group>application-peers</peer-group>
</config>
</neighbor>

5) ipv4 route

POST http://localhost:8181/restconf/config/bgp-rib:application-rib/10.25.1.10/tables/bgp-types:ipv4-address-family/bgp-types:unicast-subsequent-address-family/bgp-inet:ipv4-routes

<ipv4-route xmlns="urn:opendaylight:params:xml:ns:yang:bgp-inet">
<path-id>0</path-id>
<prefix>10.0.0.11/32</prefix>
<attributes>
<as-path></as-path>
<origin>
<value>igp</value>
</origin>
<local-pref>
<pref>100</pref>
</local-pref>
<ipv4-next-hop>
<global>10.11.1.1</global>
</ipv4-next-hop>
</attributes>
</ipv4-route>

But when I try to read peer's adj-rib-out, I get:

<adj-rib-out xmlns="urn:opendaylight:params:xml:ns:yang:bgp-rib">
<tables>
<afi xmlns:x="urn:opendaylight:params:xml:ns:yang:bgp-linkstate">x:linkstate-address-family</afi>
<safi xmlns:x="urn:opendaylight:params:xml:ns:yang:bgp-linkstate">x:linkstate-subsequent-address-family</safi>
<linkstate-routes xmlns="urn:opendaylight:params:xml:ns:yang:bgp-linkstate"></linkstate-routes>
<attributes></attributes>
</tables>
<tables>
<afi xmlns:x="urn:opendaylight:params:xml:ns:yang:bgp-types">x:ipv4-address-family</afi>
<safi xmlns:x="urn:opendaylight:params:xml:ns:yang:bgp-types">x:unicast-subsequent-address-family</safi>
<ipv4-routes xmlns="urn:opendaylight:params:xml:ns:yang:bgp-inet">
<ipv4-route>
<prefix>10.0.0.11/32</prefix>
<attributes>
<as-path></as-path>
<origin>
<value>igp</value>
</origin>
<local-pref>
<pref>100</pref>
</local-pref>
<ipv4-next-hop>
<global>10.11.1.1</global>
</ipv4-next-hop>
</attributes>
</ipv4-route>
</ipv4-routes>
<attributes></attributes>
</tables>
</adj-rib-out>

This causes troubles for Honeycomb, because such data cannot be transformed to BA as path-id is part of route's key.