The Anthropic provider in BYOK only accepts an API key

The Anthropic provider in BYOK only accepts an API key (sk-ant-) against api.anthropic.com. That means it can only draw on Anthropic Console credits, which are a separate prepaid balance from a Claude Pro/Max subscription, the two don't transfer.

Please add OAuth / subscription-based auth for the Anthropic provider, the same way Claude Code authenticates via `claude login`. Third-party apps that authenticate against a Claude subscription through the Agent SDK currently draw on subscription usage limits, so the mechanism exists.

As it stands, a paying Claude subscriber has no way to use their own plan in Copilot and has to fund a second balance to do the same work (e.g. to use Fable consumption credits).

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| Field | Value |
| --- | --- |
| App version | 1.1.12 |
| OS | Windows 10.0.26200 |
| Theme | GitHub |
| Path | /chat |
| Tenure | Week 15 |

Commencez par retracer le fournisseur BYOK Anthropic et comparer son flux de clé API avec la façon dont Claude Code s’authentifie via `claude login`. Examinez le comportement d’authentification de l’Agent SDK décrit dans l’issue. Le travail est terminé lorsque l’authentification Anthropic basée sur un abonnement fonctionne pour les abonnés Claude sans nécessiter de solde séparé de clé API.

Rédigé par le modèle d'indexation à partir du texte de l'issue.