It looks like you have only reader role access on the Synapse workspace. Due to this reason, you are unable to view the SHIR keys.
A reader role should only allow the assignee to read information on the resource it applies to.
The reason is, If we displayed the SHIR keys to a Reader, we'd be giving them the right to write to the resource by deploying a SHIR app and hooking it into synapse with that SHIR key.
To view the Self-hosted integration runtime keys in Azure Synapse Analytics, you need to have the "Synapse Administrator" or "Synapse Contributor" role assigned to your user account on the workspace level.
The "Synapse Administrator" role provides complete access to all Synapse resources, while the "Synapse Contributor" role provides access to create and manage Synapse resources but not to manage access to those resources.
I hope this helps. Please let me know if you have any further questions.
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