refactor(api): simplify MCP OAuth authorization and consent

[izadoesdev]

The scoped MCP connection flow carried the same authorization through several optional fields and used handwritten OAuth requests and response types. This cleanup uses Better Auth's native OAuth client and one required OAuth principal from the API through MCP and RPC. Consent and Connected apps now show the provider's actual client_name.

• Load the OAuth grant and user in parallel once per HTTP request and reuse the existing RPC authorization type; remove duplicate organization/scope fields and obsolete account-wide OAuth discovery helpers and redundant awaits on synchronous organization resolution.
• Store the encoded consent reference directly in request state, use TanStack Query's mutation state for consent submission, let the native OAuth client handle redirects, and keep disconnect pending until Connected apps refreshes.
• Keep organization boundaries, selected websites, approved scopes, fresh membership checks before cached discovery, and disconnect/reconnect revocation intact. Net change: 57 fewer lines, including test updates.

Validation: repository lint and all 37 typecheck/build tasks; 93 focused MCP tool and selected-site regressions; native TanStack mutation check confirming disconnect stays pending until revoked rows disappear; normal pre-push monorepo tests. The separately landed staging test-budget fix passed all 23 revenue integration cases and the full 31-task CI test workload with ClickHouse and website-reader integration enabled.

Slice: MCP OAuth authorization and consent cleanup. Based on current staging; #1032 is already merged. No unmerged dependencies. Checked open PRs; #692 touches auth initialization/storage, with no overlapping files or contracts in this slice.

Maintainer-requested change; implemented and reviewed with Codex assistance.

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated
dashboard	Ready	Preview	Oct 1, 2026 8:06pm UTC
databuddy-status	Ready	Preview	Oct 1, 2026 8:06pm UTC
documentation	Ready	Preview	Oct 1, 2026 8:06pm UTC

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: ASSERTIVE

Plan: Advanced

Run ID: bcf7178c-2b42-4cc6-93ac-117a6b6a40f0

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

• Autopilot · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

Autopilot is currently an internal CodeRabbit preview.

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[cubic-dev-ai]

All reported issues were addressed across 20 files

Architecture diagram

sequenceDiagram
    participant Client as Dashboard Client
    participant API as API Route (Elysia)
    participant Auth as Auth Service (Better Auth)
    participant MCP as MCP Handler
    participant Ctx as Tool Context
    participant RPC as RPC Layer
    participant DB as Database

    Note over Client,DB: MCP OAuth Authorization Flow

    Client->>Auth: Request /oauth2/authorize
    Auth->>Auth: mcpConsentAccess - encode consent reference
    Auth->>Auth: mcpPostLogin - store encoded reference

    Client->>Auth: POST /oauth2/consent (accept/deny)
    Auth->>Auth: Native OAuth client - validate consent
    alt Accept
        Auth-->>Client: Redirect URL
        Client->>API: MCP request with OAuth token
        API->>API: Validate token scopes (no API scope filter)
        API->>DB: Find user by subject ID
        alt User exists
            API->>MCP: handleDatabuddyMcpRequest (oauth principal + user)
            MCP->>Ctx: ensureWebsiteAccess / buildRpcContext
            Ctx->>DB: Check fresh membership
            alt Valid membership
                Ctx->>RPC: Execute tool with OAuth context
                RPC->>DB: Access websites with organization boundary
                RPC-->>Ctx: Result
                Ctx-->>MCP: Response
                MCP-->>API: Success
            else No membership
                Ctx-->>MCP: Access denied
                MCP-->>API: Unauthorized
            end
        else User not found
            API-->>Client: Unauthorized
        end
    else Deny
        Auth-->>Client: Redirect URL
    end

    Note over Client,DB: Connected Apps Display

    Client->>Auth: oauth2.getConsents (native client)
    Auth-->>Client: Consent list with clientIds
    Client->>Auth: oauth2.publicClient (per consent)
    Auth-->>Client: client metadata (client_name)
    Client->>Client: Display provider client_name

    Note over Client,DB: Disconnect/Revocation

    Client->>Auth: oauth2.deleteConsent (native client)
    Auth->>DB: Revoke OAuth grant
    DB-->>Auth: Confirmation
    Auth-->>Client: Success
    Client->>Client: Invalidate connected apps query

Loading

<sub>Shadow auto-approve: would not auto-approve because issues were found.

Re-trigger cubic</sub>

[greptile-apps]

Confidence Score: 4/5

[High risk] Refactors OAuth authorization flow and MCP request handling.

The PR appears safe to merge; adding a successful browser consent test would strengthen the redirect coverage.

Findings

1.  Consent redirect goes untested ▶

Summary

MCP OAuth now carries one user, grant, and scope record from the API through MCP tools and RPC. Consent and Connected apps use Better Auth’s OAuth client methods and display the provider’s client_name.

• Keeps organization, website, membership, and scope checks tied to the same OAuth grant.
• Stores the encoded consent choice in request state and uses native OAuth calls in the dashboard.

Diagram

%%{init: {'theme': 'neutral'}}%%
flowchart LR
  A[OAuth MCP request] --> B[Load grant and user]
  B --> C[MCP tools]
  C --> D[Check scopes and website access]
  C --> E[RPC with the same OAuth principal]
  F[Consent page] --> G[Better Auth OAuth client]
  G --> H[Consent and connected apps]

Loading

_{Reviews (1) · Last reviewed commit: "refactor(api): simplify MCP OAuth author..."}

[unkey-deploy]

The latest updates on your projects. Learn more about Unkey Deploy

Name	Status	Preview	Inspect	Updated (UTC)
links (preview)	Ready	Visit Preview	Inspect	Oct 1, 2026 8:05pm

[cubic-dev-ai]

0 issues found across 3 files (changes from recent commits).

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

<sub>Shadow auto-approve: would require human review. Refactors MCP OAuth authorization/consent to use Better Auth's native OAuth client and one required OAuth principal. Human review needed: the route now passes unfiltered token scopes into grant validation, and consent redirect handling is only partially visible.

Re-trigger cubic</sub>

[cubic-dev-ai]

0 issues found across 3 files (changes from recent commits).

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

<sub>Shadow auto-approve: would require human review. Refactors MCP OAuth authorization/consent to use Better Auth's native OAuth client with a single OAuth principal. Human review is still needed because scope enforcement in getMcpAccessGrant and consent redirect handling are not fully verifiable from the diff.

Re-trigger cubic</sub>