[FEATURE] Feature Request — Third-party OAuth support for consumer subscriptions

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Hi Anthropic team,

I'm an Open Source contributor to AmigaAI, a native Claude AI agent for AmigaOS 3.x (a classic 68k platform). It uses the Anthropic Messages API with API keys today.

Many users have Claude Pro/Max subscriptions and would like to use their existing subscription with AmigaAI rather than purchasing separate API credits. The natural solution would be OAuth2 (Device Authorization Grant / RFC 8628), which is well-suited to constrained clients that lack a full web browser.

I understand that consumer OAuth tokens are currently restricted to first-party applications (Claude.ai, Claude Code). I'd like to request that Anthropic consider offering a sanctioned third-party OAuth flow — either a developer program or a registered-client model — that would allow projects like AmigaAI to authenticate against consumer subscriptions with Anthropic's approval.

AmigaAI is a real-world example of a native platform client where API-key billing is a barrier to adoption, and where the Device Authorization Grant flow would work well technically.

Thank you for considering this.

Proposed Solution

I'd like to request that Anthropic consider offering a sanctioned third-party OAuth flow — either a developer program or a registered-client model — that would allow projects like AmigaAI to authenticate against consumer subscriptions with Anthropic's approval.

Alternative Solutions

_No response_

Priority

Critical - Blocking my work

Feature Category

Other

Use Case Example

_No response_

Additional Context

_No response_