{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "AHA hook input",
  "description": "Claude Code's hook input, in every harness; `harness` and `tool_kind` added.",
  "type": "object",
  "properties": {
    "hook_event_name": {
      "enum": [
        "SessionStart",
        "SessionEnd",
        "UserPromptSubmit",
        "PreToolUse",
        "PostToolUse",
        "Stop",
        "PreCompact"
      ]
    },
    "session_id": {
      "type": "string"
    },
    "transcript_path": {
      "type": "string"
    },
    "cwd": {
      "type": "string"
    },
    "prompt": {
      "type": "string",
      "description": "prompt submit"
    },
    "tool_name": {
      "type": "string",
      "description": "as Claude Code names it, e.g. Bash"
    },
    "tool_input": {
      "description": "as Claude Code gives it: `command` for Bash, `file_path` for a file tool"
    },
    "tool_response": {
      "description": "post tool"
    },
    "source": {
      "type": "string",
      "description": "session start"
    },
    "stop_hook_active": {
      "type": "boolean",
      "description": "stop: the agent is already continuing for a stop hook"
    },
    "last_assistant_message": {
      "type": "string"
    },
    "harness": {
      "type": "string",
      "description": "the harness that ran the hook, e.g. codex"
    },
    "tool_kind": {
      "enum": [
        "shell",
        "read",
        "write",
        "mcp",
        "other"
      ]
    }
  },
  "required": [
    "hook_event_name",
    "harness"
  ]
}