ip -br -c=never -j -f inet a show eth0 |jq -Mr '.[0].addr_info[0].local'

# ip:
#    -br       - brief output
#    -c=never  - no colors
#    -j        - output in json format
#    -f inet   - only include ipv4
# jq:
#    -M        - monochrome/no colors
#    -r        - raw output/no quotes