The prompt tooling deprecation tracker
In 2026, Anthropic and OpenAI both moved to delete the tools that helped people write instructions for their own products — Anthropic's went dark on 17 August, OpenAI's are scheduled to follow on 30 November, four months apart. Neither company said the underlying problem had gone away. Both told developers the same thing: own the artifact yourself now. This page tracks every tool in that layer that has shut down, been acquired, or pivoted since 2024 — dated, sourced, and kept current as it keeps happening.
Last updated 23 August 2026 · 12 entries · confidence tier and source link on every row
| Tool | Event | Date | Migration path | Confidence | Source |
|---|---|---|---|---|---|
| Anthropic Console Workbench | Retired, saved prompts/variables/evals not carried over | 17 Aug 2026announced 17 Jul | New stateless Playground on the Messages APIExport Workbench data by 1 Sep 2026 — after that it is unrecoverable | T1 | platform.claude.com support.claude.com |
| Anthropic prompt tools APIgenerate_prompt / improve_prompt / templatize_prompt | Retired, endpoints now error | 17 Aug 2026 | Anthropic's own suggestion: Messages API with a meta-prompt | T1 | platform.claude.com |
| OpenAI reusable prompt objectsv1/prompts | De-emphasized 3 Jun 2026, shutdown | 30 Nov 2026 | "Move reusable prompt content into your application code" | T1 | developers.openai.com |
| OpenAI Evals platform | Read-only 31 Oct, shutdown | 30 Nov 2026 | PromptfooOpenAI itself acquired Promptfoo in March 2026 — the recommended migration target is now an OpenAI product | T1 | developers.openai.com |
| OpenAI Agent Builder | Shutdown | 30 Nov 2026 | Agents SDK / ChatGPT Workspace Agents | T1 | developers.openai.com |
| OpenAI dataset-backed prompt optimizer | Deprecated alongside Evals | 30 Nov 2026 | None stated | T1 | developers.openai.com |
| Promptfoo | Acquired by OpenAI | 9 Mar 2026 | Remains open source | T1 | openai.com |
| Humanloop | Team acqui-hired by Anthropic, product sunset | 2025 | Weights & Biases | T2Date and acquirer confirmed only via secondary reporting — no primary Anthropic or Humanloop announcement found. | techcrunch.com |
| Helicone | Acquired by Mintlify, maintenance mode | 3 Mar 2026 | Mintlify | T1 | helicone.ai |
| Vellum | Pivoted to a consumer assistant after a $25M raise | 7 May 2026 | None stated | T1Launch post confirms the new product and the raise; it does not address the future of the developer platform. | vellum.ai |
| PromptPerfect | Parent Jina AI acquired by Elastic; product not named in the release | Acquisition 9 Oct 2025shutdown dates disputed | Every source citing shutdown dates sells an alternative | T1 T3T1 acquisition · T3 dates | elastic.co |
| PromptHero | Acquired by ElevenYellow, refocused on image generation | 6 Nov 2024 | n/a | T1 T3T1 ownership — ElevenYellow lists PromptHero among its products · T3 date — from the co-founder's public post, not a company notice | elevenyellow.com |
The weakest row on this page
PromptPerfect. The acquisition is solid: Elastic announced the Jina AI deal on its own blog on 9 October 2025, and that is a primary source — which is also where you can check that PromptPerfect is never named in it. The shutdown dates are not. We could not verify them against any primary Jina AI or Elastic notice — no deprecation post, no changelog entry, no status page.
Every source we found carrying a specific PromptPerfect shutdown date sells a competing prompt tool. That is a conflict of interest, not proof of anything, so the dates stay at T3 and stay flagged here rather than being quietly folded into the table above.
If you have a primary Jina AI or Elastic notice with real dates, send it and this row gets upgraded — with the source named.
Methodology
What "verified" means here. A row is verified when the event was fetched against a primary source — the vendor's own deprecation notice, changelog, docs page, status post or acquisition press release. Not a roundup, not an aggregator, not another tracker.
Every row links what it was checked against. A T1 link goes to the vendor's own notice. Where the best available evidence is press coverage rather than a company notice, the link is marked (secondary) and the row cannot be T1 — Humanloop is the current example, and the Confidence column says so on the row itself rather than in a footnote.
Rows are dated by the event, not by when we recorded it. Where a vendor announced on one date and shut down on another, both appear. A tool that was acquired but still runs is listed as acquired, not shut down — the distinction matters for whether you need to migrate.
Corrections welcome. If a row is wrong, out of date, or missing, email support@bespokeprompting.com with a primary source and it gets fixed. Tools that shut down after this page was published get added as it happens.
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