Add AgentCard to Resources — open A2A identity standard with MCP server

[kwailapt]

What is AgentCard?

AgentCard v1.0 is an open standard for agent-to-agent (A2A) identity — analogous to HTTP headers for the agent web.

• Framework-neutral JSON schema: works with LangChain, CrewAI, AutoGen, MCP, or any custom agent
• MCP server included: pip install agentcard-mcp — 4 tools + 2 resources
• Open standard: Apache 2.0 + CC-BY 4.0, patent non-reservation

Why this belongs in Resources

AgentCard provides the identity layer that lets MCP agents identify themselves and each other in multi-agent systems. It's not just another MCP server — it's a protocol standard that MCP servers can implement to declare compliance.

What's changed

Added one line to the 📚 Resources section (alphabetically between "A2A-MCP Java Bridge" and "AiMCP"):

- **[AgentCard](https://github.com/kwailapt/AgentCard)** - Open standard for agent-to-agent (A2A) identity: declare capabilities, resolve peers, and validate agent cards using a framework-neutral JSON schema. Analogous to HTTP headers for the agent web. Includes MCP server (`pip install agentcard-mcp`), LangChain/CrewAI/AutoGen adapters, and JSON Schema. Apache 2.0. by **[kwailapt](https://github.com/kwailapt)**

Links

• Spec + schema: https://github.com/kwailapt/AgentCard
• JSON Schema: https://github.com/kwailapt/AgentCard/blob/main/schema.json
• MCP server: https://github.com/kwailapt/AgentCard/tree/main/adapters/python/mcp-server
• LangChain/CrewAI/AutoGen adapters: https://github.com/kwailapt/AgentCard/tree/main/adapters/python

MCP server tools

Tool	Description
agentcard_declare	Register an agent's identity (AgentCard JSON)
agentcard_resolve	Look up a peer by name or ULID
agentcard_validate	Validate against AgentCard v1.0 schema
agentcard_list	List all registered agents

Resources: agentcard://schema, agentcard://registry

[kwailapt]

Hi maintainers,

I noticed the CI check failed with HttpError: Resource not accessible by integration (403 on the labels endpoint) — this appears to be a permissions issue on your workflow side when triggered from a fork, not an issue with this PR's content.

Clarification on this PR's intent:

This PR adds one line to the 📚 Resources section (not the servers list). AgentCard is a protocol standard / identity schema, analogous to how HTTP headers work — it's a resource/tool for the MCP ecosystem, not a competing server:

• Open standard for A2A agent identity (JSON schema, Apache 2.0)
• MCP server included: pip install agentcard-mcp (4 tools + 2 resources)
• Framework adapters for LangChain, CrewAI, AutoGen
• Already submitted to the MCP Server Registry (io.github.kwailapt/agentcard)

Since this is a Resources section entry and not a new server being added to a removed server list, I believe it falls outside the scope of the "no longer accepting server PRs" policy.

Happy to adjust the wording if helpful. Thanks for the review!