API sunsets · Twilio · checked

Twilio Flex UI 2.16.x end of life on 31 October 2026

Twilio Flex UI 2.16.x reaches end of life on 31 October 2026. After it, no more fixes or security updates, and it may stop working as intended. Nothing fails on the day, so the change is silent: calls keep working, with no fixes and no guarantee. Twilio names 2.18.x as the replacement (the supported version on 8 October 2026; Twilio recommends turning on automatic minor updates). Record your real calls on 2.16.x before the date and replay them on 2.18.x: after it, 2.16.x can change or stop without notice. Find every place your code pins 2.16.x: npx --allow-git=root github:agentwares/api-sunset scan

$ npx --allow-git=root github:agentwares/api-sunset scan

npx --allow-git=root github:agentwares/api-sunset scan lists every API version your code and config pin (Shopify, Meta Graph, Google Ads, HubSpot, Stripe and the rest of this list) with its end date, what breaks and this page's link. It needs no account and no API key, reads your files on your machine and sends nothing; its one request fetches this data. Free and MIT licensed.

The facts

API
Twilio Flex UICovers Flex UI 2.x versions (@twilio/flex-ui).
Version
2.16.xReleased 18 February 2026.
Ends
31 October 2026
After the date
unsupported
Silent?
Yes: no error is returned
Replacement
2.18.xthe supported version on 8 October 2026; Twilio recommends turning on automatic minor updates

What breaks after 31 Oct 2026

How to upgrade

  1. Find every place your code and config pin 2.16.x: npx --allow-git=root github:agentwares/api-sunset scan prints each file and line, and the variable name for a .env file, never its value.
  2. Read what changed between 2.16.x and 2.18.x in Twilio's notes, and list the calls that touch it.
  3. Before 31 October 2026, send your real calls to 2.16.x and to 2.18.x and compare the answers: same status, same fields, same values where they should match; after it, 2.16.x can change or stop without notice.
  4. Change the version string, deploy, and watch the first day's responses.

Record your real calls on the old version before the date, and replay them on the new one.

agentcheck runs scheduled checks of an endpoint. A check sends the request you define (a path or a full URL, a method and a body, with your API key as a header, stored encrypted) on a schedule and compares each response with a golden: exact text, contains, a regular expression or a JSON Schema, none of which costs an LLM call. When a response stops matching, it opens an incident and alerts you. Point one check at 2.16.x and one at 2.18.x with the same golden, and you see which of your calls answer differently before 31 October 2026.

Free: 1 monitored target, hourly checks, badge and public status page. Starter: 3 targets, 5-minute checks, Slack and Discord alerts, 30-day history. Recording the calls your code already makes is a different path: the trace import (POST /api/v1/targets/{id}/traces, or the agentcheck_record MCP tool) takes agent traces, a prompt and an answer, and turns them into checks judged by the LLM judge (Pro). It does not take raw HTTP requests and responses, so for an API the scheduled checks are the way in today.

Migration watch is not built. It would record the calls your code makes to Twilio Flex UI 2.16.x and replay them on 2.18.x until 31 October 2026, with nothing to set up, and email you what answers differently. If you would pay for that, say so with one click. The click is counted; nothing else is sent or stored.

Other Twilio dates

Every API sunset, by date

Sources

Built only from Twilio's own pages. No intent is implied: a date is what the page says on the day it was read. Data: /apis/sunsets.json.

api-sunset is a free tool from agentcheck, which runs scheduled checks of your endpoints and alerts you when an answer changes.