public void setTool(String tool) {

		this.tool = tool;
		this.normalizedExternalToolName = tool;

		if (this.tool != null && this.tool.toUpperCase().startsWith("IDA-PRO")) {
			this.normalizedExternalToolName = "IDA-PRO";
		}
		else if (this.tool != null && this.tool.toUpperCase().startsWith("GHIDRA")) {
			this.normalizedExternalToolName = null;  //"GHIDRA";  // null, not external
		}

	}
Sets tool field.
Also sets normalizedExternalToolName to normalized tool names "IDA-PRO" or "GHIDRA" if appropriate, or just sets it to the value of tool.
Ghidra/Features/Sarif/src/main/java/sarif/managers/ProgramInfo.java