{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://open-agent-harness.dev/schemas/hook.schema.json",
  "title": "Open Agent Harness Hook Definition",
  "type": "object",
  "additionalProperties": false,
  "required": [
    "name",
    "events",
    "handler"
  ],
  "properties": {
    "name": {
      "type": "string",
      "minLength": 1,
      "pattern": "^[a-zA-Z0-9._-]+$"
    },
    "events": {
      "type": "array",
      "minItems": 1,
      "items": {
        "type": "string",
        "enum": [
          "before_context_build",
          "after_context_build",
          "before_model_call",
          "after_model_call",
          "before_tool_dispatch",
          "after_tool_dispatch",
          "run_completed",
          "run_failed"
        ]
      },
      "uniqueItems": true
    },
    "matcher": {
      "type": "string",
      "minLength": 1
    },
    "handler": {
      "oneOf": [
        {
          "$ref": "#/$defs/commandHandler"
        },
        {
          "$ref": "#/$defs/httpHandler"
        },
        {
          "$ref": "#/$defs/promptHandler"
        },
        {
          "$ref": "#/$defs/agentHandler"
        }
      ]
    },
    "capabilities": {
      "type": "array",
      "items": {
        "type": "string",
        "enum": [
          "rewrite_context",
          "rewrite_model_request",
          "rewrite_model_response",
          "rewrite_tool_request",
          "rewrite_tool_response",
          "suppress_output"
        ]
      },
      "uniqueItems": true
    }
  },
  "$defs": {
    "promptSource": {
      "type": "object",
      "additionalProperties": false,
      "oneOf": [
        {
          "required": [
            "inline"
          ]
        },
        {
          "required": [
            "file"
          ]
        }
      ],
      "properties": {
        "inline": {
          "type": "string",
          "minLength": 1
        },
        "file": {
          "type": "string",
          "minLength": 1
        }
      }
    },
    "commandHandler": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "type",
        "command"
      ],
      "properties": {
        "type": {
          "const": "command"
        },
        "command": {
          "type": "string",
          "minLength": 1
        },
        "cwd": {
          "type": "string"
        },
        "timeout_seconds": {
          "type": "integer",
          "minimum": 1
        },
        "environment": {
          "type": "object",
          "additionalProperties": {
            "type": "string"
          }
        }
      }
    },
    "httpHandler": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "type",
        "url"
      ],
      "properties": {
        "type": {
          "const": "http"
        },
        "url": {
          "type": "string",
          "format": "uri"
        },
        "method": {
          "type": "string",
          "enum": [
            "GET",
            "POST",
            "PUT",
            "PATCH",
            "DELETE"
          ]
        },
        "headers": {
          "type": "object",
          "additionalProperties": {
            "type": "string"
          }
        },
        "timeout_seconds": {
          "type": "integer",
          "minimum": 1
        }
      }
    },
    "promptHandler": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "type",
        "prompt"
      ],
      "properties": {
        "type": {
          "const": "prompt"
        },
        "prompt": {
          "$ref": "#/$defs/promptSource"
        },
        "model_ref": {
          "type": "string",
          "minLength": 1
        },
        "timeout_seconds": {
          "type": "integer",
          "minimum": 1
        }
      }
    },
    "agentHandler": {
      "type": "object",
      "additionalProperties": false,
      "required": [
        "type",
        "agent",
        "task"
      ],
      "properties": {
        "type": {
          "const": "agent"
        },
        "agent": {
          "type": "string",
          "minLength": 1
        },
        "task": {
          "$ref": "#/$defs/promptSource"
        },
        "timeout_seconds": {
          "type": "integer",
          "minimum": 1
        }
      }
    }
  }
}