Hi,
Agents establish a connection using the jnlp command when the secret key first 32 characters are provided instead of the all 64-characters secret key.
e.g.
following is command line provided by jenkins to connect agent to jenkins node

java -jar [agent.jar](Jenkins URL/jnlpJars/agent.jar) -jnlpUrl Jenkins URL/computer//jenkins-agent.jnlp -secret 9b52b3f7ad1fb603bee7315d0644adc98965038fcf44672be9dc053c59ee0448

but if I remove last 32 charector of secret key, It still getting connected.

java -jar [agent.jar](Jenkins URL/jnlpJars/agent.jar) -jnlpUrl Jenkins URL/computer//jenkins-agent.jnlp -secret 9b52b3f7ad1fb603bee7315d0644adc9

using jenkins version 2.332.3