{"id":"INC-github-24t8gsgqx2qb","kind":"incident","aliases":[],"related":[],"title":"GitHub: Errors with the Fable 5 Model in Copilot","description":"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.","summary":null,"severity":"medium","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"GitHub","fixed":[],"affected":"","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["ci","git","github","incident","ops","vendor"],"not_affected_if":[],"how_to_check":null,"fix":null,"status":"resolved","published_at":"2026-08-13T14:43:25+00:00","first_seen_at":"2026-10-23T19:12:22+00:00","triaged_at":"2026-10-23T21:55:04+00:00","updated_at":"2026-10-23T21:55:04+00:00","category":"vendor","confidence":null,"triage":null,"analyst_status":null,"analyst_note":null,"search":"'06':28C '12':63C '13th':23C '14':27C '15':30C '2026':24C '24t8gsgqx2qb':13A '43':60C '47':31C '5':6A,43C 'altern':69C 'approxim':26C 'august':22C 'auto':67C 'averag':62C 'ci':15B 'claud':41C 'copilot':9A,34C 'degrad':38C 'due':45C 'elev':55C 'encount':54C 'error':2A,56C 'experienc':36C 'fabl':5A,42C 'futur':105C 'git':16B 'github':1A,12A,14A,17B,85C 'improv':93C 'inc':11A 'inc-github-24t8gsgqx2qb':10A 'incid':18B,102C 'issu':48C,73C 'mitig':78C 'model':7A,44C,70C 'op':19B 'peak':58C 'place':81C 'prevent':100C 'provid':52C,84C,90C 'put':79C 'rate':57C 'resili':95C 'resolv':75C 'select':66C 'servic':35C,98C 'similar':101C 'unaffected.the':72C 'upstream':51C 'user':53C,64C 'utc':32C 'vendor':20B 'work':87C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2026-08-13T14:43:25+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"statuspage","external_id":"github:24t8gsgqx2qb","url":"https://stspg.io/8htrnxk0q09v","severity":"medium","published_at":"2026-08-13T14:43:25+00:00","modified_at":"2026-08-25T12:08:46+00:00","first_seen_at":"2026-10-23T19:12:22+00:00","fetched_at":"2026-10-25T14:58:55+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}