[Bug] Anthropic API Error: Invalid or Inaccessible Model claude-fable-5
Status Closed — not planned
Reported on v2.1.176
Maintainer reply None cached
Activity 13 comments · opened Jun 13, 2026 · closed Aug 1, 2026
Bug Description
⏺ There's an issue with the selected model (claude-fable-5). It may not exist or you may not have access to it. Run /model to pick a different model.
Environment Info
- Platform: darwin
- Terminal: iTerm.app
- Version: 2.1.176
- Feedback ID: 46bb8dd9-668f-4114-93fe-5e06d0135efc
Errors
[{"error":"Error: 404 {\"type\":\"error\",\"error\":{\"type\":\"not_found_error\",\"message\":\"Claude Fable 5 is not available. Please use Opus 4.8. Learn more: https://www.anthropic.com/news/fable-mythos-access\"},\"request_id\":\"req_011CbzRzhVfPy6yesub42QVa\"}\n at generate (/$bunfs/root/src/entrypoints/cli.js:12:67578)\n at makeRequest (/$bunfs/root/src/entrypoints/cli.js:52:7694)\n at processTicksAndRejections (native:7:39)","timestamp":"2026-06-13T01:59:13.506Z"},{"error":"Error: 404 {\"type\":\"error\",\"error\":{\"type\":\"not_found_error\",\"message\":\"Claude Fable 5 is not available. Please use Opus 4.8. Learn more: https://www.anthropic.com/news/fable-mythos-access\"},\"request_id\":\"req_011CbzS5Jo3oGGd9bacMgTSn\"}\n at generate (/$bunfs/root/src/entrypoints/cli.js:12:67578)\n at makeRequest (/$bunfs/root/src/entrypoints/cli.js:52:7694)\n at processTicksAndRejections (native:7:39)","timestamp":"2026-06-13T02:00:15.994Z"},{"error":"Error: 404 {\"type\":\"error\",\"error\":{\"type\":\"not_found_error\",\"message\":\"Claude Fable 5 is not available. Please use Opus 4.8. Learn more: https://www.anthropic.com/news/fable-mythos-access\"},\"request_id\":\"req_011CbzSF7btHEq3wVTtvE5Na\"}\n at generate (/$bunfs/root/src/entrypoints/cli.js:12:67578)\n at makeRequest (/$bunfs/root/src/entrypoints/cli.js:52:7694)\n at processTicksAndRejections (native:7:39)","timestamp":"2026-06-13T02:02:29.268Z"},{"error":"Error: 404 {\"type\":\"error\",\"error\":{\"type\":\"not_found_error\",\"message\":\"Claude Fable 5 is not available. Please use Opus 4.8. Learn more: https://www.anthropic.com/news/fable-mythos-access\"},\"request_id\":\"req_011CbzSJesQSTpmdu8wtMqgU\"}\n at generate (/$bunfs/root/src/entrypoints/cli.js:12:67578)\n at makeRequest (/$bunfs/root/src/entrypoints/cli.js:52:7694)\n at processTicksAndRejections (native:7:39)","timestamp":"2026-06-13T02:03:17.329Z"}]Showing cached comments. Read the full discussion on GitHub ↗
12 Comments
Same issue, happened ~just now
oh, same issue
https://github.com/anthropics/claude-code/issues/68123
https://github.com/anthropics/claude-code/issues/68126 and others
Happened to me, too. Via Claude Code CLI:
There's an issue with the selected model (claude-fable-5). It may not exist or you may not have access to it. Run /model to pick a different model.Closed and restarted Claude Code to no avail. Started a new session (not a resume) but got the same result. Had to switch to Opus 4.8 to finish my tasks.
Yes it happens in web, cli or app with the same error message like -
There's an issue with the selected model (claude-fable-5). It may not exist or you may not have access to it.Fable 5 & Mythos 5 have been disabled for all users. Anthropic was forced to do this by the US government:
https://www.anthropic.com/news/fable-mythos-access
<img width="1234" height="479" alt="Image" src="https://github.com/user-attachments/assets/bbfcafe4-20ce-4013-9b91-7b56e07568f4" />
Same for me.
Will they extend their 22nd deadline because of this?
Why would you break all your models. You are told to disable one and all your infrastructure goes to shit?
+1
FIX:
Check what the current advisor model is (/advisor).
If you see Fable, use the /advisor command to switch to a different model
/advisor isn't available in this environment.