Claude-fable-5 fails with routing_unsupported (requires non-ZDR provider policy) even with own API key — direct API call succeeds

[Showa]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Since June 12 (JST), every request to claude-fable-5 fails. It worked fine until June 11. Other models (GPT, other Claude models) work fine — only claude-fable-5 fails.
Full error:
Request ID: 404a74c7-aeae-4f1e-8d17-e7d7685364b2
{“error”:“ERROR_OPENAI”,“details”:{“title”:“Unable to reach the model provider”,“detail”:“We encountered an issue when using your API key: Provider was unable to process your request\n\nAPI Error:\n\nRequest failed with status code 400: {"error":{"type":"client","reason":"routing_unsupported","message":"claude-fable-5 routing failed: requires non-ZDR provider policy","retryable":false}}”}}
What I have verified:

My own Anthropic API key is enabled in Cursor (used for all claude- models), and the error confirms it is being used (“when using your API key”)
My Anthropic org has 30-day data retention ON (not ZDR), confirmed in Claude Console
A direct curl to api.anthropic.com with a key from the same workspace succeeds with claude-fable-5
Privacy Mode is OFF (Share Data: Active)

So the same key works when calling Anthropic directly, but fails with a ZDR routing policy error when the request goes through Cursor. This started around June 12; my build is dated 2026-06-10, so it may be related to the 3.7.27 update.
Version: 3.7.27
VS Code Extension API: 1.105.1
Commit: e48ee6102a199492b0c9964699bf011886708ba0
Date: 2026-06-10T01:46:16.942Z
Build Type: Stable
OS: Darwin arm64 25.5.0 (macOS, Apple Silicon)

Steps to Reproduce

1. Enable own Anthropic API key in Cursor Settings → Models (key is verified and active)
2. Select claude-fable-5 in the chat/agent model picker
3. Send any prompt
4. Request fails immediately with the routing_unsupported error above (100% reproducible since June 12 JST)

Expected Behavior

claude-fable-5 should respond normally, as it did until June 11, and as it does when calling the Anthropic API directly with the same key.

Operating System

MacOS

Version Information

Version: 3.7.27
VS Code Extension API: 1.105.1
Commit: e48ee6102a199492b0c9964699bf011886708ba0
Date: 2026-06-10T01:46:16.942Z
Build Type: Stable
OS: Darwin arm64 25.5.0

For AI issues: which model did you use?

claude-fable-5

For AI issues: add Request ID with privacy disabled

Request ID: 404a74c7-aeae-4f1e-8d17-e7d7685364b2

Additional Information

Using my own Anthropic API key. Same key succeeds when calling the Anthropic API directly. Details in the bug description above.

Does this stop you from using Cursor

No - Cursor works, but with this issue

[quazo]

Same here

[vidhuvidz (V8181)]

same

[Chaitanya_Yalavarthi]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Until this afternoon I could use Fable 5 in the Cursor IDE with the following setup, and it worked fine:

Plan: Pro+
Custom Anthropic API key (from console.anthropic.com; account has standard 30‑day retention, i.e. non‑ZDR)
Cursor Privacy Mode: Active
Fable 5 data‑retention policy acknowledged (modelId: claude-fable-5, consentVersion: fable-data-retention-v1)
As of this afternoon, with no change on my end, every Fable 5 request now fails with a 400:

{“error”:{“type”:“client”,“reason”:“routing_unsupported”,“message”:“claude-fable-5 routing failed: requires non-ZDR provider policy”,“retryable”:false}}
Routing now insists on a non‑ZDR provider policy even though my Fable 5 data‑retention consent was acknowledged, which previously satisfied this exact combination (Privacy Mode + custom non‑ZDR key + acknowledged consent).

This looks possibly related to the existing report about the stored noZdrModelConsents Fable consent record being mishandled server‑side ([the noZdrModelConsents cannot be set via updateTeamAdminSettings thread]).

What I’ve already tried (none resolved it)

Re‑confirmed Fable 5 shows “Data Policy Acknowledged” in dashboard → Settings → Privacy.
Switched Privacy Mode from Active to Share Data (disabled Privacy Mode). After this, the Fable 5 acknowledgement section disappeared (expected), but the 400 still persists.
Full quit + reopen of Cursor; waited for propagation.
Confirmed my Anthropic key is non‑ZDR (30‑day retention is ON in the Anthropic console).

Steps to Reproduce

Pro+ account, add a custom Anthropic API key (non‑ZDR / 30‑day retention).
Enable Cursor Privacy Mode (Active).
Acknowledge the Fable 5 data‑retention policy and use claude-fable-5.
Worked previously; now every request returns the 400 routing_unsupported / requires non-ZDR provider policy.
Disabling Privacy Mode (Share Data active) does not fix it.
Operating System macOS

Operating System

MacOS

Version Information

Version: 3.7.27 (Universal)
VS Code Extension API: 1.105.1
Commit: e48ee6102a199492b0c9964699bf011886708ba0
Date: 2026-06-10T01:46:16.942Z
Layout: editor
Build Type: Stable
Release Track: Default
Electron: 39.8.1
Chromium: 142.0.7444.265
Node.js: 22.22.1
V8: 14.2.231.22-electron.0
xterm.js: 6.1.0-beta.256
OS: Darwin arm64 25.2.0

For AI issues: which model did you use?

Fable5

Does this stop you from using Cursor

No - Cursor works, but with this issue

[quazo]

I’m experiencing this exact thing as well!

[Taeyoung_Park (002)]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

I’m using claude-fable-5 with my own API key in Cursor. It was working fine until a few hours ago, but it suddenly stopped and now returns the error below. The same API key works perfectly with claude-fable-5 when called outside of Cursor, so I suspect that something in the request parameters Cursor sends to Claude conflicts with the non-ZDR 30-day retention policy. Updating to the latest version did not solve anything.

I’ve been a heavy Cursor user since the very beginning and have even taught it to many of my students, so it’s really disappointing and frustrating that Fable 5 fails only inside Cursor. Could you please look into this and fix it?
Error message:
We encountered an issue when using your API key: Provider was unable to process your request
API Error:
Request failed with status code 400: {“error”:{“type”:“client”,“reason”:“routing_unsupported”,“message”:“claude-fable-5 routing failed: requires non-ZDR provider policy”,“retryable”:false}}

Steps to Reproduce

Setup your own claude API key
Set the model to claude fable 5
Prompt anything from the IDE

Operating System

Windows 10/11

Version Information

Cursor IDE 3.7.27

Does this stop you from using Cursor

Yes - Cursor is unusable

[quazo]

I’m experiencing this as well.

[vidhuvidz (V8181)]

same issue

[Alex_Lee1 (Alex Lee)]

same here

[groa]

same here!

[vitmush (Vitaly)]

same here, it worked great last time I know 19 hours ago

[Colin]

Thanks for the reports, everyone! I’ve raised this to our dev team.

[JP99 (John Priday)]

exact same issue

[Colin]

Hey all!

We did actually ship a fix for this. However, as many of you are likely aware, Fable is not generally available at the moment.

Claude Fable 5 - Out Now!

Hey everyone! As you’ve well noticed, Fable is currently not accessible in Cursor or otherwise. Completely understandable and acceptable to discuss the circumstances around this, and we also ask the conversation remain civil and in the spirit of our community guidelines. This is not directed at any comment made so far, just a reminder for future discussion.

Thank you again for the reports.