Resources/read does not return content, specified by [McpMeta] attribute, resources/list does

[Ponomareff]

Describe the bug
Resources/read does not return content, specified by [McpMeta] attribute, resources/list does

To Reproduce
Steps to reproduce the behavior:

1. Attach attribute [McpMeta("ui", JsonValue = """{ "csp": { "resourceDomains": ["https://cdn.jsdelivr.net"] } }""")] to method, marked with [McpServerResource]
2. Using MCP Inspector: resources/list returns _meta attribute value above
3. Using MCP Inspector: resources/read does not

Expected behavior
resources/read returns content of [McpMeta] attribute along with uri, mimeType and text

Additional context
Bug in src\ModelContextProtocol.Core\Server\AIFunctionMcpServerResource.cs method ReadAsync results do not initialize Meta property of returned results

[stephentoub]

Thanks for the issue.

Most of the SDKs don't do this:
#1230 (comment)

Can you elaborate on the need?

[Ponomareff]

Thanks for the issue.

Most of the SDKs don't do this: #1230 (comment)

Can you elaborate on the need?

Short answer: MCP-Apps require this by specification. I confirmed it by fixing on local branch.

https://github.com/modelcontextprotocol/ext-apps/blob/main/specification/2026-01-26/apps.mdx