Errors with the Fable 5 Model in Copilot
Aug 13, 14:43 UTCAug 13, 15:47 UTC
Duration
1h 4m
Impact
Minor
Root cause
Dependency
GitHub, 90 days
68 incidents
Affected
Copilot AI Model Providers
Final update
On August 13th, 2026, between approximately 14:06 and 15:47 UTC, the Copilot service experienced a degradation of the Claude Fable 5 model due to an issue with our upstream provider. Users encountered elevated error rates, peaking at 43% and averaging 12%. Users who selected Auto or alternative models were unaffected. The issue was resolved by a mitigation put in place by our provider. GitHub is working with our provider to further improve the resiliency of the service to prevent similar incidents in the future.
Timeline
- Resolved · Aug 13, 15:47 UTC
On August 13th, 2026, between approximately 14:06 and 15:47 UTC, the Copilot service experienced a degradation of the Claude Fable 5 model due to an issue with our upstream provider. Users encountered elevated error rates, peaking at 43% and averaging 12%. Users who selected Auto or alternative models were unaffected. The issue was resolved by a mitigation put in place by our provider. GitHub is working with our provider to further improve the resiliency of the service to prevent similar incidents in the future.
- Investigating · Aug 13, 15:47 UTC
The issues with our upstream model provider have been resolved, and Fable 5 is once again available in Copilot products and IDE surfaces. We will continue monitoring to ensure stability, but mitigation is complete.
- Investigating · Aug 13, 15:23 UTC
We are seeing modest recovery, but are still experiencing degraded availability for the Fable 5 model in Copilot products and IDE surfaces. This is due to an issue with an upstream model provider. While we work with them to resolve the issue, we recommend choosing another model or selecting 'Auto' to continue using Copilot.
- Investigating · Aug 13, 14:50 UTC
We are experiencing degraded availability for the Fable 5 model in Copilot products and IDE surfaces. This is due to an issue with an upstream model provider. While we work with them to resolve the issue, we recommend choosing another model or selecting 'Auto' to continue using Copilot.
- Investigating · Aug 13, 14:43 UTC
We are investigating reports of degraded performance for Copilot AI Model Providers
More from GitHub
Full history| Started | Incident | Impact | Duration |
|---|---|---|---|
| Sep 2310:11 UTC | Incident across several services | minor | Ongoing |
| Sep 2022:13 UTC | Incident with Pull Requests | minor | 1h 9m |
| Sep 1720:59 UTC | Elevated rate of errors for OpenAI models provided by Copilot | minor | 50m |
| Sep 1607:20 UTC | Degradation with Gemini 3.8 Flash | major | 10h 28m |
| Sep 1519:11 UTC | Disruption with some GitHub services | minor | 49m |
| Sep 1509:47 UTC | Disruption with some GitHub services | minor | 1h 30m |
Also caused by third-party dependency
All| Started | Vendor | Incident | Impact | Duration |
|---|---|---|---|---|
| Sep 1609:48 UTC | Support Portal Service Disruption | minor | 11h 21m | |
| Sep 1608:31 UTC | Support Helpdesk Availability Issues | minor | 6h 27m | |
| Sep 417:03 UTC | Degradation of Hosted Grafana in US Central Region | major | 3h 39m | |
| Sep 416:05 UTC | Elevated Linux worker queue times | major | 15h 4m | |
| Sep 115:25 UTC | Investigating issues in US Central (prod-us-central-0, prod-us-central-5) | minor | 4h 54m | |
| Aug 3106:26 UTC | Packet loss in ORD | minor | 1h 44m |
From vendors' own status pages and disclosures. Times as reported. Logos via logo.dev; trademarks belong to their owners.