Allow setting default values for optional DCR values

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Ory Network Project

No response

Describe your problem

When using Dynamic Client Registration (DCR), Hydra responds with empty values (empty string or empty array) for optional client values such as:

• client_uri
• logo_uri
• contacts
• tos_uri
• policy_uri

Several MCP clients (python-mcp and typescript-mcp) validate these values and often fail with an error stating that the provided value is not valid (empty string is not a valid url, ...). While Hydra allows setting these values when creating a new client manually, they are always empty when using DCR.

Describe your ideal solution

I suggest we should be able to either set default values for these fields via the configuration file, or hydra should not respond with these fields at all if they are not set.

Workarounds or alternatives

Some links which discuss this problem:

• https://github.com/modelcontextprotocol/typescript-sdk/issues/940 (workaround for some of the fields, but not all)
• https://github.com/modelcontextprotocol/typescript-sdk/issues/543 (validation issue for contacts)
• https://github.com/open-webui/open-webui/pull/19144/files (workaround in application using a MCP client)

Version

v25.4.0

Additional Context

No response