Go to Jobs->Your Job -> Configuration Tab -> click Json on the right hand of the screen.

click on Jobs. Click on the name of the job. next to the job name you should see a RUN NOW and a MORE button. Click More and select view JSON.

If you're using the UI then see the previous responses. If you want to use the CLI then you would use the following.

# Get list of jobs
databricks jobs list
 
# Get JSON for specific job
databricks jobs get --job-id <job id>

If you're trying to do it in an automated way then you can use the Jobs API.

I join to post's thread. I'd like to have the same but in the notebooks, not by CLI:

Is it possible to passthrough job's parameters to variable? (databricks.com)