function createDebugBodyPreview(text, limit) {
  if (text.length <= limit) return { value: text || "(empty response body)", truncated: false };
  try {
    const normalized = text.replace(/^\uFEFF/, "").trimStart()
      .replace(/^\)\]\}',?\s*/, "").replace(/^while\s*\(1\);\s*/, "");
    let value = JSON.parse(normalized);
    for (let depth = 0; depth < 2 && typeof value === "string" && /^\s*[\[{]/.test(value); depth += 1) {
      try { value = JSON.parse(value); } catch { break; }
    }
    // Bound retained data without cutting JSON syntax or losing sensitive field names.
    let remaining = Math.max(0, limit - 256);
    const visit = (node, depth = 0) => {
      if (remaining <= 64 || depth >= 30) return "[omitted from debug preview]";
      if (node === null || typeof node !== "object") {
        const serialized = JSON.stringify(node);
        if (serialized.length > remaining) {
          remaining = 0;
          return "[omitted from debug preview]";
        }
        remaining -= serialized.length + 1;
        return node;
      }
      const result = Array.isArray(node) ? [] : Object.create(null);
      remaining -= 2;
      for (const key of Object.keys(node)) {
        const cost = Array.isArray(node) ? 1 : JSON.stringify(key).length + 2;
        if (remaining < cost + 64) break;
        remaining -= cost;
        result[key] = visit(node[key], depth + 1);
      }
      return result;
    };
    return {
      value: JSON.stringify({ debugNotice: "Partial response preview: remaining fields/items omitted due to the debug size limit.", preview: visit(value) }),
      truncated: true
    };
  } catch {
    return { value: `${text.slice(0, limit)}\n... truncated ${text.length - limit} characters`, truncated: true };
  }
}