Suggestion: add Agent Card MCP resource generation capabilities to MCPAdapt

From my current understanding of https://google.github.io/A2A/#/topics/a2a_and_mcp?id=intersection and the recommendation to have MCP servers expose an agent card resource, it could be interesting to leverage [MCPAdapt](https://github.com/grll/mcpadapt) to be able to generate that resource consistently across agentic framework.

MCPAdapt is making it seamless to use MCP servers tools in many agentic framework including langchain / langgraph, crewAI, smolagents, google genai sdk... Similarly to A2A it provides cross agentic framework capabilities so what I am thinking is we could add an option for people using MCPAdapt with an adapter on specific agentic framework A to easily spawn a MCP server that would expose that recommended resource. Thanks to MCPAdapt this could be leveraged across all agentic framework.

Would that make sense?

Review the A2A documentation on agent card MCP resources and the MCPAdapt repository to understand its adapter architecture. Identify where resource generation logic would be added to expose the agent card. Determine how to make this an optional feature across supported frameworks like langchain and crewAI.

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