{
  "version": "2.0.0",
  "protocol_family": "FCS-4.0",
  "protocol_version": "4.0",
  "description": "Current interfaces and explicit implementation limits. Supersedes the 2025-12-18 skill contract.",
  "skills": [
    {
      "id": "run_self_demo",
      "name": "Contract Demo",
      "status": "implemented",
      "description": "Checks locally served discovery, skill references, and declared topology. Makes no external fetches and performs no trust verification.",
      "invoke": {
        "method": "POST",
        "uri": "https://agentjson.org/invoke/demo",
        "content_type": "application/json"
      },
      "input_schema": {
        "type": "object",
        "additionalProperties": false,
        "properties": {
          "mode": {
            "type": "string",
            "enum": [
              "default",
              "verbose",
              "minimal"
            ],
            "default": "default"
          }
        }
      },
      "output_schema": {
        "type": "object",
        "properties": {
          "sequence": {
            "const": "completed"
          },
          "protocol_version": {
            "const": "FCS-4.0"
          },
          "mode": {
            "type": "string"
          },
          "steps": {
            "type": "array",
            "items": {
              "type": "object",
              "properties": {
                "action": {
                  "type": "string"
                },
                "uri": {
                  "type": "string"
                },
                "status": {
                  "type": "string"
                }
              },
              "required": [
                "action",
                "uri",
                "status"
              ]
            }
          },
          "trust_verification": {
            "const": "not_performed"
          },
          "external_requests": {
            "const": 0
          }
        },
        "required": [
          "sequence",
          "protocol_version",
          "mode",
          "steps",
          "trust_verification",
          "external_requests"
        ]
      }
    },
    {
      "id": "verify_agent",
      "name": "Agent Trust Verification",
      "status": "not_implemented",
      "description": "Reserved interface. A request receives HTTP 501, no trust score, and no verified lineage.",
      "invoke": {
        "method": "POST",
        "uri": "https://agentjson.org/invoke/verify",
        "content_type": "application/json",
        "expected_status": 501
      },
      "input_schema": {
        "type": "object",
        "properties": {},
        "additionalProperties": false
      },
      "output_schema": {
        "type": "object",
        "properties": {
          "error": {
            "const": "verification_not_implemented"
          },
          "verified": {
            "const": false
          },
          "trust_score": {
            "type": "null"
          },
          "lineage_verified": {
            "const": false
          }
        },
        "required": [
          "error",
          "verified",
          "trust_score",
          "lineage_verified"
        ]
      }
    },
    {
      "id": "resolve_capability",
      "name": "Local Capability Directory",
      "status": "implemented",
      "description": "Returns AgentJSON capabilities and resource URLs. No filtering or remote-agent resolution.",
      "invoke": {
        "method": "GET",
        "uri": "https://agentjson.org/.well-known/agent-discovery.json"
      },
      "input_schema": {
        "type": "object",
        "properties": {},
        "additionalProperties": false
      },
      "output_schema": {
        "type": "object",
        "properties": {
          "capabilities": {
            "type": "array",
            "items": {
              "type": "string"
            }
          },
          "endpoints": {
            "type": "object"
          }
        },
        "required": [
          "capabilities",
          "endpoints"
        ]
      }
    },
    {
      "id": "navigate_mesh",
      "name": "Read Declared Neighbors",
      "status": "implemented",
      "description": "Reads the current FCS-4.0 topology. The caller may follow explicit links; coordinates and recursive traversal are not implemented.",
      "invoke": {
        "method": "GET",
        "uri": "https://agentjson.org/constellation.json"
      },
      "input_schema": {
        "type": "object",
        "properties": {},
        "additionalProperties": false
      },
      "output_schema": {
        "type": "object",
        "properties": {
          "domain": {
            "type": "string"
          },
          "protocol": {
            "const": "FCS-4.0"
          },
          "neighbors": {
            "type": "array",
            "items": {
              "type": "object",
              "properties": {
                "domain": {
                  "type": "string"
                },
                "relation": {
                  "type": "string"
                }
              },
              "required": [
                "domain",
                "relation"
              ]
            }
          }
        },
        "required": [
          "domain",
          "protocol",
          "neighbors"
        ]
      }
    }
  ],
  "meta": {
    "total_skills": 4,
    "implemented_skills": 3,
    "unavailable_skills": 1,
    "protocol_version": "FCS-4.0",
    "invocation_model": "REST-JSON",
    "authentication": {
      "required": false,
      "enhanced_access": false
    }
  },
  "timestamps": {
    "created": "2025-12-18T05:10:00Z",
    "updated": "2026-09-29"
  },
  "migration": {
    "previous_version": "1.0.0",
    "previous_protocol": "FCS-3.0",
    "breaking_changes": [
      "Removed unsupported inputs and invented trust outputs.",
      "navigate_mesh now references current topology instead of historical Helix mesh.",
      "Demo output describes actual local checks."
    ]
  },
  "resource_type": "current_invocation_registry"
}