Unable to have multiple projects within the same account share standard BYO resources - Capability host provisioning fails

[bhavadeepk]

Hi all,

I have been using the standard-agent-setup bicep files to deploy a new foundry account and a project. Initial setup has created Search, CosmosDB and Storage resources. It also created connections to the project, added roles and capability host settings were configured correctly for the account and the first project. I was able to view the data that was flowing into the resources while engaging with agents.

Now that I have that working, I have been trying to add a new project to the same account and trying to connect to the same shared resources by giving the resource Ids of the already created search, cosmos and storage accounts. Initially had few issues since the connections with the same names had a conflict since they have been registered with that name at the account level, so I changed the connection names for the new project but pointing to the same underlying resources.

But where it fails is deploying a new capability host for the new project with the new connections.

{
  "id": "/subscriptions/{subscription}/resourceGroups/{rg}/providers/Microsoft.CognitiveServices/accounts/foundry-deployment-frameworkj7ry/projects/project-deployment-test-new/capabilityHosts/caphostacc",
  "name": "caphostacc",
  "properties": {
    "aiServicesConnections": null,
    "capabilityHostKind": "Agents",
    "customerSubnet": null,
    "description": null,
    "properties": null,
    "provisioningState": "Failed",
    "storageConnections": [
      "dplmtfwm7gjstorage-test-new"
    ],
    "tags": null,
    "threadStorageConnections": [
      "dplmt-fw-fgu6cosmosdb-test-new"
    ],
    "vectorStoreConnections": [
      "dplmt-fw-m7gjsearch-test-new"
    ]
  },
  "systemData": {
    "createdAt": "2025-07-23T18:52:26.1877436+00:00",
    "lastModifiedAt": "2025-07-23T18:52:30.5950381+00:00"
  },
  "type": "Microsoft.CognitiveServices/accounts/projects/capabilityHosts"
}

I have tried multiple other ways :

1. Tried to add the connections in the account capability host with/without project overrides
2. To use management apis to delete and re-create capability hosts but none seem to work. It also seem to break the new project agent service, where in the portal I see

Unable to access your agents
Service temporarily unavailable. Please try again later
Trace ID : 7b920ad8-7314-4bff-850d-baf01bdd9cc9
Client request ID : 2630a58b-fc71-4335-a8fb-1d64d2aeb580
APIM request ID : 5199a8c8-557c-4cf9-a1d5-0527b8ef636b

So my question is,
Is it possible to share standard resources across multiple projects within an account? Or is it intended to only be isolated for each project?
If it is possible, can you please share some samples on how to do that?

[ckittel]

Great question/observation! I've only every tried single set of BYO dependencies per project, not a shared set per account (or even more brave, single resource shared across accounts). The GUIDs used in the index and storage and Cosmos DB collections makes me think it should support multiple projects and probably even accounts.

Following.