Learn how to troubleshoot your tracing setup.

If you need help managing transactions, you can read more here. If you need additional help, you can ask on GitHub. Customers on a paid plan may also contact support.

When Sentry captures transactions, they are assigned a transaction name. This name is generally auto-generated by the Sentry SDK based on the framework integrations you are using. If you can't leverage the automatic transaction generation (or want to customize how transaction names are generated) you can use a global event processor that is registered when you initialize the SDK with your configuration.

For example:

// All JavaScript-based SDKs include this function, so it's safe to replace `@sentry/node`
// with your particular SDK
import { addEventProcessor } from "@sentry/node";

addEventProcessor((event) => {
  if (event.type === "transaction") {
    event.transaction = sanitizeTransactionName(event.transaction);
  return event;

For browser JavaScript applications using the BrowserTracing integration, the beforeStartSpan option can be used to better group navigation/pageload transactions together based on URL.

import * as Sentry from "@sentry/browser";

  // ...
  integrations: [
      beforeStartSpan: (context) => {
        return {
          // You could use your UI's routing library to find the matching
          // route template here. We don't have one right now, so do some basic
          // parameter replacements.
          name: location.pathname
            .replace(/\/[a-f0-9]{32}/g, "/<hash>")
            .replace(/\/\d+/g, "/<digits>"),

Currently, every tag has a maximum character limit of 200 characters. Tags over the 200 character limit will become truncated, losing potentially important information. To retain this data, you can split data over several tags instead.

For example, a 200+ character tag like this:

...will become truncated to:

Instead of using tags, it is recommended to add data to spans as attributes. Using span.setAttribute() allows to add data with arbitrary length to a span. You can add as many attributes to your span as you want.

const baseUrl = "";
const endpoint = "/api/0/projects/ep/setup_form";
const parameters = {
  user_id: 314159265358979323846264338327,
  tracking_id: "EasyAsABC123OrSimpleAsDoReMi",
  product_name: PlantToHumanTranslator,
  product_id: 161803398874989484820458683436563811772030917980576,

    op: "http.client",
    name: "setup form",
    // you can add attributes when starting the span
    attributes: {
  (span) => {
    // or you can add attributes to an existing span
    for (const key of parameters) {
      span.setAttribute(`parameters.${key}`, parameters[key]);

    // do something to be measured
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