# MCPF Initialize Response - Expected Format

## Request Format
```bash
curl -X POST http://localhost:8787/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d '{
    "jsonrpc": "2.0",
    "method": "initialize",
    "params": {
      "protocolVersion": "2025-03-26",
      "capabilities": {},
      "clientInfo": {
        "name": "test-client",
        "version": "1.0"
      }
    },
    "id": 1
  }'
```

## Response Format (SSE Stream)

The server returns Server-Sent Events (SSE) format:

```
event: message
data: {JSON_RESPONSE}
```

## Complete JSON Response Structure

```json
{
  "result": {
    "protocolVersion": "2025-03-26",
    "capabilities": {
      "tools": {
        "listChanged": true
      }
    },
    "serverInfo": {
      "name": "kisc-arch-kultura-valodu-mcp",
      "version": "0.2.0"
    },
    "_meta": {
      "identity": {
        "id": "did:web:llm.kis.gov.lv",
        "service": {
          "mcp": "https://llm.kis.gov.lv/mcp"
        },
        "keys": {
          "jwks_uri": "https://llm.kis.gov.lv/.well-known/jwks.json"
        }
      },
      "mcpf": {
        "version": "0.1",
        "spec": {
          "repository": "https://github.com/MCPTrustFramework/MCPF-specification"
        },
        "entrypoint": {
          "type": "manifest",
          "url": "https://llm.kis.gov.lv/.well-known/mcp/manifest.json"
        },
        "artifacts": {
          "trust_registry": "https://llm.kis.gov.lv/.well-known/mcp-trust-registry.json",
          "credential": "https://veritrust.vc/portal/mcp/credentials/aec9930b-9139-4b33-ac6f-ad3bd3d91da0.json"
        }
      },
      "trust": {
        "verifications": [
          {
            "verifier": "did:web:veritrust.vc",
            "type": [
              "VerifiableCredential",
              "MCPServerVerification"
            ],
            "credential": "https://veritrust.vc/portal/mcp/credentials/aec9930b-9139-4b33-ac6f-ad3bd3d91da0.json",
            "covers": "did:web:llm.kis.gov.lv",
            "proof_hint": {
              "verificationMethod": "did:web:veritrust.vc#key-1",
              "created": "2026-01-29T10:12:41Z"
            }
          }
        ]
      }
    }
  },
  "jsonrpc": "2.0",
  "id": 1
}
```

## MCPF Layer 1: Session-Level Trust Metadata

The `_meta` field contains three key sections:

### 1. Identity
```json
{
  "id": "did:web:llm.kis.gov.lv",
  "service": {
    "mcp": "https://llm.kis.gov.lv/mcp"
  },
  "keys": {
    "jwks_uri": "https://llm.kis.gov.lv/.well-known/jwks.json"
  }
}
```

**Purpose:** Establishes the server's decentralized identity (DID) and key material location.

### 2. MCPF Metadata
```json
{
  "version": "0.1",
  "spec": {
    "repository": "https://github.com/MCPTrustFramework/MCPF-specification"
  },
  "entrypoint": {
    "type": "manifest",
    "url": "https://llm.kis.gov.lv/.well-known/mcp/manifest.json"
  },
  "artifacts": {
    "trust_registry": "https://llm.kis.gov.lv/.well-known/mcp-trust-registry.json",
    "credential": "https://veritrust.vc/portal/mcp/credentials/aec9930b-9139-4b33-ac6f-ad3bd3d91da0.json"
  }
}
```

**Purpose:** Links to MCPF specification and trust artifacts for agent discovery.

### 3. Trust Verifications
```json
{
  "verifications": [
    {
      "verifier": "did:web:veritrust.vc",
      "type": ["VerifiableCredential", "MCPServerVerification"],
      "credential": "https://veritrust.vc/portal/mcp/credentials/aec9930b-9139-4b33-ac6f-ad3bd3d91da0.json",
      "covers": "did:web:llm.kis.gov.lv",
      "proof_hint": {
        "verificationMethod": "did:web:veritrust.vc#key-1",
        "created": "2026-01-29T10:12:41Z"
      }
    }
  ]
}
```

**Purpose:** Documents third-party verification by VeriTrust credential service.

## Verification Steps

An MCPF-aware agent should:

1. **Extract DID** from `_meta.identity.id`
2. **Resolve DID document** at `https://llm.kis.gov.lv/.well-known/did.json`
3. **Fetch verification credential** from VeriTrust
4. **Verify credential signature** using VeriTrust's public key
5. **Check credential subject** matches server DID
6. **Optionally fetch** trust registry and manifest for additional context

## Test with jq

Extract specific fields:

```bash
# Get the DID
curl ... | grep '^data:' | sed 's/^data: //' | jq -r '.result._meta.identity.id'
# Output: did:web:llm.kis.gov.lv

# Get MCPF version
curl ... | grep '^data:' | sed 's/^data: //' | jq -r '.result._meta.mcpf.version'
# Output: 0.1

# Get verifier DID
curl ... | grep '^data:' | sed 's/^data: //' | jq -r '.result._meta.trust.verifications[0].verifier'
# Output: did:web:veritrust.vc

# Get credential URL
curl ... | grep '^data:' | sed 's/^data: //' | jq -r '.result._meta.trust.verifications[0].credential'
# Output: https://veritrust.vc/portal/mcp/credentials/aec9930b-9139-4b33-ac6f-ad3bd3d91da0.json
```

## Notes

- The `_meta` field is **in addition to** standard MCP initialize response fields
- Backward compatible: non-MCPF clients ignore `_meta`
- Layer 1 (session-level) + Layer 2 (per-response attestations) = Dual-layer trust
- Session ID returned in `Mcp-Session-Id` response header (not shown in JSON)