{
  "$id": "https://mcpcontracts.com/schema/0.1.0.json",
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "MCP Contract Manifest",
  "description": "Manifest format for MCP Contract bundles — declares layers, typed contracts, and composition rules.",
  "type": "object",
  "required": ["name", "version", "layers"],
  "properties": {
    "$schema": {
      "type": "string",
      "description": "JSON Schema URI for this manifest format."
    },
    "name": {
      "type": "string",
      "pattern": "^[a-z0-9-]+$",
      "description": "Bundle name. Lowercase, hyphens only."
    },
    "version": {
      "type": "string",
      "pattern": "^\\d+\\.\\d+\\.\\d+",
      "description": "Semantic version of the bundle."
    },
    "description": {
      "type": "string",
      "description": "Human-readable description of what this bundle does."
    },
    "author": {
      "type": "object",
      "properties": {
        "name": { "type": "string" },
        "url": { "type": "string", "format": "uri" }
      },
      "required": ["name"]
    },
    "license": {
      "type": "string",
      "description": "SPDX license identifier."
    },
    "extends": {
      "type": "array",
      "description": "External layer dependencies for cross-author composition.",
      "items": {
        "type": "object",
        "required": ["package", "version", "layer"],
        "properties": {
          "package": {
            "type": "string",
            "description": "Package identifier (e.g., @alice/diligence-prompts)."
          },
          "version": {
            "type": "string",
            "description": "Semver range (e.g., ^1.0.0)."
          },
          "layer": {
            "type": "string",
            "enum": ["prompts", "tools", "apps", "skills"],
            "description": "Which layer this dependency provides."
          }
        }
      }
    },
    "layers": {
      "type": "object",
      "description": "Layer declarations with entry points and contracts.",
      "properties": {
        "prompts": {
          "$ref": "#/$defs/promptLayer"
        },
        "tools": {
          "$ref": "#/$defs/toolLayer"
        },
        "apps": {
          "$ref": "#/$defs/appLayer"
        },
        "skills": {
          "$ref": "#/$defs/skillLayer"
        }
      },
      "additionalProperties": false
    },
    "compiler_compatibility": {
      "type": "array",
      "items": { "type": "string" },
      "description": "List of LLM compilers this bundle is compatible with."
    },
    "compose": {
      "type": "object",
      "properties": {
        "chain": {
          "type": "array",
          "items": {
            "type": "string",
            "enum": ["prompts", "tools", "apps"]
          },
          "description": "Execution order of layers."
        },
        "fallback": {
          "type": "string",
          "description": "Fallback mode if some layers are unavailable (e.g., 'prompts-only')."
        }
      }
    }
  },
  "$defs": {
    "contractEntry": {
      "type": "object",
      "required": ["name", "schema"],
      "properties": {
        "name": {
          "type": "string",
          "description": "Contract name — used to match provides to consumes across layers."
        },
        "schema": {
          "type": "string",
          "description": "Relative path to a JSON Schema file defining the contract shape."
        },
        "description": {
          "type": "string",
          "description": "Human-readable description of what this contract represents."
        }
      }
    },
    "promptLayer": {
      "type": "object",
      "required": ["entry"],
      "properties": {
        "entry": {
          "type": "string",
          "description": "Relative path to the primary prompt Markdown file."
        },
        "modules": {
          "type": "array",
          "items": { "type": "string" },
          "description": "Additional prompt modules."
        },
        "provides": {
          "type": "array",
          "items": { "$ref": "#/$defs/contractEntry" },
          "description": "Schemas this layer provides."
        }
      }
    },
    "toolLayer": {
      "type": "object",
      "required": ["entry"],
      "properties": {
        "entry": {
          "type": "string",
          "description": "Relative path to the MCP server entry point."
        },
        "runtime": {
          "type": "string",
          "enum": ["node", "python", "go", "rust"],
          "description": "Runtime for the tool server."
        },
        "dependencies": {
          "type": "string",
          "description": "Relative path to dependency manifest (package.json, requirements.txt, etc.)."
        },
        "provides": {
          "type": "array",
          "items": { "$ref": "#/$defs/contractEntry" },
          "description": "Schemas this layer provides."
        }
      }
    },
    "appLayer": {
      "type": "object",
      "required": ["entry"],
      "properties": {
        "entry": {
          "type": "string",
          "description": "Relative path to the primary app component."
        },
        "modules": {
          "type": "array",
          "items": { "type": "string" },
          "description": "Additional app modules."
        },
        "consumes": {
          "type": "array",
          "items": { "$ref": "#/$defs/contractEntry" },
          "description": "Schemas this layer consumes from other layers."
        }
      }
    },
    "skillLayer": {
      "type": "object",
      "required": ["targets"],
      "properties": {
        "targets": {
          "type": "object",
          "additionalProperties": {
            "type": "string",
            "description": "Relative path to the platform-specific skill Markdown file."
          },
          "description": "Map of compiler target to skill file path."
        }
      }
    }
  }
}