Migrate MCP registry from v0 to v0.1 API specification

[Copilot]

The MCP registry client was using the deprecated v0 API endpoint. The v0.1 specification introduces a significantly different response structure and field naming conventions per the official OpenAPI schema.

Changes

API Endpoint

• https://api.mcp.github.com/v0 → https://api.mcp.github.com/v0.1

Response Structure

Before (v0):

{
  "servers": [{
    "name": "example/server",
    "status": "active",
    "packages": [{
      "registry_type": "npm",
      "transport": {"type": "stdio"}
    }]
  }]
}

After (v0.1):

{
  "servers": [{
    "server": {
      "name": "example/server",
      "packages": [{
        "registryType": "npm",
        "transport": {"type": "stdio"}
      }]
    },
    "_meta": {
      "io.modelcontextprotocol.registry/official": {
        "status": "active"
      }
    }
  }]
}

Type System Updates (mcp_registry_types.go)

• Added ServerResponse wrapper with server and _meta fields
• Renamed fields to match OpenAPI spec: registry_type → registryType, runtime_hint → runtimeHint, etc.
• Changed Transport from string to object
• Added nullable pointers for Repository and Transport
• Enhanced Argument type with additional fields from spec

Parsing Logic (mcp_registry.go)

• Updated SearchServers and GetServer to unwrap nested response structure
• Status extraction moved from top-level status to _meta["io.modelcontextprotocol.registry/official"]["status"]
• Added null safety checks for pointer fields

Tests

• Updated mock responses in 3 test files to match v0.1 structure
• All existing tests pass without functional changes
• Added comprehensive live integration tests (mcp_registry_live_test.go) that validate against the production registry:
  • TestMCPRegistryClient_LiveSearchServers: Tests fetching and filtering servers from live API
  • TestMCPRegistryClient_LiveGetServer: Tests retrieving specific servers with complete metadata
  • TestMCPRegistryClient_LiveResponseStructure: Validates v0.1 field parsing with real data
  • All tests skip gracefully on network restrictions and pass with live v0.1 API

Original prompt

Review MCP registry lookup and package resolution support according to the latest specificatin and file format supported by the github mcp registry.

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[pelikhan]

@copilot add tests against live registry.

[Copilot]

@copilot add tests against live registry.

Added comprehensive live integration tests in commit 6b3982b. The new test file mcp_registry_live_test.go includes:

TestMCPRegistryClient_LiveSearchServers:

• Validates fetching 30+ servers from production registry
• Tests query filtering (e.g., 11 servers matching "github")
• Verifies transport type distribution (stdio: 21, sse: 6, streamable-http: 3)

TestMCPRegistryClient_LiveGetServer:

• Retrieves and validates real servers with complete metadata
• Tests error handling for nonexistent servers

TestMCPRegistryClient_LiveResponseStructure:

• Confirms v0.1 field parsing (packageArguments, environmentVariables, runtimeHint)
• Validates transport types across all 30 servers

All tests skip gracefully on network restrictions and pass with the live v0.1 API.