I created a custom agent and can see it in my app, where it performs activities as expected. However, I am unable to view the Agent Access tab. To check, I navigated to Setup → Agentforce Agents, selected the agent, and opened the Agentforce Builder.

 The Agent Access tab may not be visible because its availability can depend on your Salesforce org configuration, permissions, and the Agentforce features enabled in your environment. Check that your user has the required Agentforce admin permissions and that you're using a supported org/release configuration. If the agent works but the tab is missing, comparing your permissions with the official setup requirements is a good next step.