Social Sign-In
Let users sign in with an identity they already have.
What it adds
OAuth used as authentication: first-time account creation from a provider identity, safe matching to existing accounts, and handling providers that return incomplete or unverified data.
What your agent is told to do
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What your agent is told to do
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Key the account on the provider's stable subject identifier, not on the email address. Emails change hands; subject IDs do not.
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Only auto-link to an existing account when the provider asserts the email is verified. An unverified email from a provider is an account-takeover route — send those users through an ownership check instead.
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Request the minimum scopes needed to identify someone. Sign-in does not need calendar or contact access.
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Handle missing profile fields as normal: many providers return no name, no avatar, and some return no email at all. Do not block account creation on data you cannot guarantee.
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Adding or removing a sign-in method on an already-authenticated account is owned by Account Linking, and OAuth for data access is owned by OAuth Integration Connections. Extend those rather than duplicating them here.
Edge cases it handles
6
Edge cases it handles
6- A user who revoked access at the provider must get a clear reconnect prompt, not a generic failure, and must still be able to sign in another way.
- Two providers returning the same email must not silently become two accounts — or one account, without an explicit decision.
- The provider changing a user's email must not orphan the account or create a duplicate.
- A cancelled or denied consent screen returns an error, not a crash; land the user back on sign-in with an explanation.
- State must be validated on the callback, and the returned state must match a value tied to the originating session.
- The first sign-in for a brand-new user must still complete any required onboarding, not drop them into a half-configured account.
Definition of done
8
Definition of done
8- Accounts are keyed on the provider subject identifier.
- Auto-linking happens only for provider-verified email addresses.
- Only identity scopes are requested.
- Missing name, avatar, or email does not block account creation.
- Denied consent and revoked access produce clear, recoverable states.
- The callback rejects mismatched or missing state.
- The feature matches the existing design system.
- No existing functionality is broken.
Related features
User Roles
User Roles
Not everyone should be able to do everything.
What it does
Role-based permissions, enforced on the server, with a UI that reflects them.
How it works
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Define roles and their permissions in ONE place. Scattering
if user.admin?through the codebase is how authorization bugs happen. - 2 Enforce every permission server-side, at the controller or service layer.
- 3 Hide UI the user can't use — but never rely on hiding as the enforcement.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/user-roles
Workspace Deletion Workflow
Workspace Deletion Workflow
Close a whole workspace without one click erasing everyone's work.
What it does
An owner-only deletion flow with an explicit inventory, a recovery window, and cascading cleanup across internal and external systems.
How it works
- 1 Restrict deletion to owners and require recent re-authentication plus typing the workspace name. This is the most destructive action in the product and should feel like it.
- 2 Show an inventory before confirming: how many members lose access, what happens to billing, how many files and records are affected, which integrations disconnect, and which shared links die.
- 3 Schedule the deletion rather than executing it. Mark the workspace as pending deletion, block access to it, notify every member and admin, and only purge after a stated recovery window.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/workspace-deletion-workflow
Domain Verification
Domain Verification
Prove an organization controls a domain before unlocking domain-wide powers.
What it does
A DNS or file-based challenge that verifies domain ownership and gates features like enforced SSO and domain-wide join.
How it works
- 1 Generate a unique, unguessable token per organization and domain, and verify it via a DNS TXT record or a file served over HTTPS at a fixed path.
- 2 Check the challenge server-side from the app's own infrastructure. A verification the browser performs can be faked.
- 3 Re-check verified domains on a schedule and mark a domain unverified when the evidence disappears, rather than trusting a one-time pass forever.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/domain-verification
How it works
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1
Copy the link
Grab the Markdown instruction URL for this feature.
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2
Give it to your AI
Paste it into Claude Code, Cursor, v0, Lovable — whatever you build with.
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3
It inspects, then implements
Your agent reads your existing app first, then adds the feature to fit it.
Works with your stack
These instructions are written to adapt. They tell the agent to detect your framework, match your existing design system, and reuse what you already have — rather than assuming a particular stack.
Need it tighter than that? Customize the feature and tell it exactly what you're running.