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Robert Saylor
Robert Saylor

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How to Build a ChatGPT GPT Action with Laravel, OAuth, and Two Separate Applications

What if your users could operate your Laravel application simply by talking to ChatGPT?

Not by copying information from ChatGPT into your application.

Not by embedding another chatbot into your website.

I mean allowing ChatGPT to securely authenticate as a user and execute real actions against your Laravel API.

I recently worked through exactly this type of integration while building a GPT Action for a production Laravel application.

The final architecture allows a user to say something as simple as:

Show me my connected social channels.

ChatGPT authenticates through OAuth, calls the Laravel API, resolves the OAuth identity to the correct application user, verifies the requested scope, and returns that user's actual data.

The architecture looks roughly like this:

ChatGPT
    ↓
Custom GPT Action
    ↓
OAuth 2.0
    ↓
Laravel Authentication Application
    ↓
Laravel Passport
    ↓
Account Mapping
    ↓
Main Laravel Application
    ↓
Application API
    ↓
User's Data
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It works.

Getting all of those pieces working together, however, exposed several implementation details that aren't immediately obvious when you start experimenting with GPT Actions.

In this article, I'll walk through the architecture, OAuth flow, OpenAPI schema, Laravel Passport configuration, account linking, scopes, debugging, deployment problems, and one very important ChatGPT account limitation you should understand before planning to distribute a GPT publicly.

And if you're reading this because you want to add ChatGPT Actions, AI integrations, OAuth, APIs, or other custom functionality to an existing Laravel application, that's exactly the kind of work we do at Custom PHP Design.

👉 Custom Laravel and PHP Development:

Custom PHP Design

What Is a GPT Action?

A custom GPT can do much more than generate text.

GPT Actions allow a GPT to communicate with external APIs.

That means a GPT can potentially:

  • Retrieve customer account information
  • Query application data
  • Create records
  • Update records
  • Start workflows
  • Publish content
  • Retrieve reports
  • Schedule tasks
  • Interact with internal business systems
  • Trigger Laravel jobs and services
  • Work with existing SaaS functionality

The GPT learns what your application can do through an OpenAPI specification.

For example:

openapi: 3.1.0

info:
  title: "Example Application API"
  version: 1.0.0

servers:
  - url: https://example.com

paths:
  /api/v1/channels:
    get:
      operationId: getConnectedChannels
      summary: Get the authenticated user's connected channels

      responses:
        '200':
          description: "Connected channels"
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Once imported into the GPT Action configuration, ChatGPT understands that it has an operation named:

getConnectedChannels
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The model can decide to call that operation when the user asks something like:

What accounts do I have connected?

This creates a very interesting interface for existing Laravel applications.

Instead of forcing every workflow through forms, dashboards, and navigation menus, some workflows can become conversational.

That doesn't mean replacing your application interface with ChatGPT.

It means giving customers another way to interact with the functionality you've already built.

If you already have a mature Laravel application and want to explore this type of integration, visit:

Custom PHP Design

Why OAuth Matters

For public application data, a GPT Action can potentially operate without user authentication.

But most useful SaaS applications contain user-specific data.

Suppose two customers use your GPT.

Customer A should see:

Customer A's data
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Customer B should see:

Customer B's data
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Customer A must never be able to access Customer B's information.

The GPT therefore needs to authenticate each user independently.

That's where OAuth comes in.

A typical OAuth Action requires:

Client ID
Client Secret
Authorization URL
Token URL
Scopes
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For Laravel, Laravel Passport is a natural option because it provides a full OAuth2 server implementation.

Our configuration ultimately looked conceptually like:

Authorization URL:
https://auth.example.com/oauth/authorize

Token URL:
https://auth.example.com/oauth/token
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The GPT receives its own OAuth client:

Client ID
Client Secret
Redirect URI
Grant Types
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The important grant types were:

authorization_code
refresh_token
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The refresh token is particularly important because you don't want customers authenticating again every time ChatGPT needs to call your API.


Why We Used Two Laravel Applications

This implementation had an additional architectural challenge.

The primary application and OAuth server were separate Laravel codebases.

Think of them as:

main-application
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and:

auth-application
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The main application contained:

  • Customer accounts
  • Business logic
  • API endpoints
  • User data
  • Application permissions
  • Existing API authentication

The Auth application contained:

  • Laravel Passport
  • OAuth clients
  • Authorization codes
  • Access tokens
  • Refresh tokens
  • OAuth authorization
  • External identity mapping

There are several reasons you might end up with this architecture.

You might want authentication isolated from the main application.

You may already have a separate authentication service.

You may be modernizing a legacy Laravel application.

You may want several applications to eventually use the same OAuth provider.

Whatever the reason, separating the applications creates an important question:

How does an OAuth user in the Auth application map back to the correct user in the main Laravel application?

That became one of the most important parts of this integration.


The Account Linking Problem

Imagine this situation.

Your primary Laravel application contains:

Main Laravel Application

users
----------------
id = 123
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Your OAuth application has its own users table:

Auth Laravel Application

users
----------------
id = 456
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ChatGPT receives an OAuth access token associated with:

Auth User 456
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But your main application's API needs to know:

Main Application User 123
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Those aren't inherently the same identity.

You need a trusted mapping between them.

Conceptually:

Auth User 456
        ↓
account_links
        ↓
Application User 123
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A linking table can represent that relationship:

application_account_links

auth_user_id
application_user_id
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Then OAuth token introspection can return something conceptually like:

{
    "active": true,
    "linked": true,
    "application_user_id": 123,
    "scopes": [
        "profile",
        "channels.read",
        "posts.read",
        "posts.write"
    ]
}
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The main Laravel application can now authenticate the incoming API request as User 123.

This is the bridge between:

ChatGPT OAuth identity
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and:

Your actual Laravel customer
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Never Trust a Browser-Supplied User ID

This part is critical.

You should never build account linking like this:

/connect?user_id=123
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and blindly trust that ID.

An attacker could simply change it to:

/connect?user_id=124
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Instead, the main Laravel application should cryptographically assert the identity.

We accomplished this with a short-lived signed handoff.


Signed Laravel-to-Laravel Account Handoff

The main application generates a short-lived signed token containing claims such as:

{
    "iss": "example.com",
    "sub": "123",
    "aud": "auth.example.com",
    "iat": 1787540000,
    "exp": 1787540300,
    "jti": "unique-random-value"
}
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The important claim is:

sub
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That represents the canonical user ID from the main application.

The token is signed using RSA SHA-256:

RS256
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The architecture becomes:

Main Laravel Application

Private Key
    ↓
Sign handoff token
    ↓

Auth Laravel Application

Public Key
    ↓
Verify signature
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The private signing key remains with the application generating the identity assertion.

The Auth application only needs the public key to verify it.

This gives the Auth application cryptographic proof that:

The main application says this request belongs to User 123.

That's considerably safer than trusting browser-supplied identifiers.


Validate More Than the Signature

Verifying the RSA signature is necessary.

It isn't sufficient.

The Auth application should validate claims such as:

alg
kid
iss
aud
iat
exp
sub
jti
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For example:

alg = RS256
issuer = expected application
audience = expected Auth service
expiration = still valid
subject = valid canonical user ID
jti = unique
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Do not allow:

alg = none
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Do not silently accept an unexpected algorithm.

Do not accept expired handoffs.

Do not trust the subject until after signature verification.

The point of the handoff is to create a small, explicit trust boundary between the two Laravel applications.


Prevent Replay Attacks

A valid signed handoff should generally be redeemable only once.

That's why we included:

jti
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The Auth application records each redeemed JTI.

For example:

handoff_redemptions

id
jti
application_user_id
redeemed_by_auth_user_id
redeemed_at
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The database should enforce uniqueness on:

jti
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Now, if somebody attempts to reuse the exact same handoff, Auth can reject it.

This provides replay protection even if somebody somehow obtains a previously valid handoff URL.


The User Shouldn't Know You Have Two Laravel Applications

Our initial implementation exposed an interesting UX problem.

The Auth application behaved like a normal standalone Laravel application.

A user arriving without an Auth session would see:

Login
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Technically, that made sense.

From a product perspective, it didn't.

The customer already has an account in the main application.

Why should they create another account and another password just because we decided to use a separate OAuth service internally?

They shouldn't.

The better experience is:

User logs into main Laravel application
        ↓
Connect ChatGPT
        ↓
Main application creates signed handoff
        ↓
Auth verifies handoff
        ↓
Auth resolves or provisions internal identity
        ↓
Account mapping created
        ↓
OAuth authorization continues
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The Auth user becomes an implementation detail.

The customer doesn't need to know it exists.

This is an important lesson when building authentication systems.

There is a difference between:

technically correct authentication

and:

good authentication UX.


Automatically Provisioning the Internal OAuth User

If your OAuth server requires its own local user record, you can automatically provision that internal identity after verifying the signed handoff.

Conceptually:

$link = AccountLink::where(
    'application_user_id',
    $verifiedSubject
)->first();

if ($link) {
    $authUser = $link->authUser;
} else {
    $authUser = createInternalAuthUser();

    AccountLink::create([
        'auth_user_id' => $authUser->id,
        'application_user_id' => $verifiedSubject,
    ]);
}
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The actual implementation should be transactional and enforce uniqueness.

The important idea is that the user doesn't have to manually register with your OAuth service.

Their identity has already been established by the trusted main application.


OAuth Scopes Are Worth Doing Properly

Don't give the GPT unlimited API access.

Use OAuth scopes.

For example:

profile
channels.read
posts.read
posts.write
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Your Laravel API routes can then require specific scopes.

Conceptually:

Route::get('/connected-channels', ...)
    ->middleware('external-scope:channels.read');
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Publishing endpoints might require:

posts.write
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Reading existing posts might require:

posts.read
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This gives you a clean permission boundary.

If you later introduce:

analytics.read
billing.read
account.write
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those capabilities can remain unavailable unless explicitly authorized.

This is especially important with AI integrations because you should expose only the capabilities the AI client actually needs.


Your Existing Laravel API Doesn't Have to Be Replaced

Our main application already had its own API authentication.

We didn't want ChatGPT OAuth support to break or replace existing API clients.

Instead, the API middleware could support multiple authentication paths.

Conceptually:

Incoming API Request
        ↓
Existing API key?
        ↓ yes
Authenticate normally

        ↓ no

External OAuth bearer token?
        ↓
Ask Auth application to introspect token
        ↓
Resolve application user
        ↓
Apply OAuth scopes
        ↓
Continue request
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This allows existing integrations to continue working while ChatGPT uses OAuth.

That's an important architectural principle:

Add AI integration capabilities without unnecessarily rewriting working application infrastructure.

At Custom PHP Design, this is how we approach Laravel modernization projects: integrate with what already works instead of automatically assuming the entire application needs to be rebuilt.

Learn more:

Custom PHP Design

Token Introspection Between Laravel Applications

The main application should not directly query Passport's database.

That would tightly couple the two applications.

Instead:

Main Application
       ↓
Server-to-server request
       ↓
Auth Application
       ↓
Passport token validation
       ↓
Account mapping
       ↓
Introspection response
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The request should use a server-to-server secret.

For example:

X-Application-Auth-Secret
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The browser never sees this value.

ChatGPT never sees this value.

It exists strictly between your servers.

The main application sends the OAuth access token to the Auth service for validation.

Conceptually:

{
    "token": "oauth-access-token"
}
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The Auth application returns something similar to:

{
    "active": true,
    "linked": true,
    "application_user_id": 123,
    "scopes": [
        "channels.read",
        "posts.read",
        "posts.write"
    ]
}
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Now your normal Laravel middleware can resolve:

User::findOrFail($applicationUserId);
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and continue processing the API request.


Don't Put Server Secrets in the Browser

This deserves its own section.

Your introspection secret should never appear in:

JavaScript
HTML
Blade data attributes
localStorage
sessionStorage
query strings
frontend API calls
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The communication should be:

ChatGPT
    ↓ bearer token
Main Laravel API
    ↓ private server-to-server request
Auth Laravel Application
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Not:

Browser
    ↓ secret
Auth Application
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Keep internal authentication internal.


A Tiny Header Name Cost Us Debugging Time

One of the bugs we encountered was painfully simple.

One Laravel application sent a header similar to:

X-Application-Introspection-Secret
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while the Auth application expected something similar to:

X-Application-Auth-Secret
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The result?

401 Unauthorized
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Everything else was correct:

  • The bearer token existed
  • OAuth worked
  • The account was linked
  • The API route existed
  • The scope existed
  • The GPT was making the request

But the server-to-server authentication failed before token introspection could happen.

The lesson:

Standardize internal authentication headers and configuration names.

Better yet, encapsulate server-to-server communication inside a service class instead of scattering raw HTTP requests throughout your Laravel application.


Safe Diagnostic Logging Is Extremely Helpful

When debugging OAuth, logging everything is tempting.

Don't.

Never log:

access_token
refresh_token
client_secret
private keys
shared secrets
authorization codes
signed handoff tokens
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Instead, log state.

For example:

{
    "external_introspection_attempted": "yes",
    "introspection_http_status": 200,
    "introspection_active": "yes",
    "introspection_linked": "yes",
    "resolved_application_user_id": 123,
    "scopes": [
        "channels.read"
    ],
    "auth_result": "external_oauth"
}
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That tells you almost everything you need without leaking credentials.

During development, this was invaluable.

We could watch the request move through:

ChatGPT
→ Auth
→ Main API
→ Introspection
→ User resolution
→ Scope validation
→ Controller
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When something failed, we knew exactly which boundary was failing.


File Permissions Can Break OAuth Too

Another production issue had almost nothing to do with OAuth protocol logic.

Laravel Passport's RSA keys had incorrect filesystem permissions after deployment.

Instead of:

600
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a Passport key ended up with:

644
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The OAuth library rejected it.

The result appeared upstream as:

500 Internal Server Error
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The fix was straightforward:

sudo chown www-data:www-data storage/oauth-private.key
sudo chown www-data:www-data storage/oauth-public.key

sudo chmod 600 storage/oauth-private.key
sudo chmod 600 storage/oauth-public.key
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But fixing it manually isn't enough.

Your deployment process should enforce it.

For example:

echo "Setting Laravel runtime permissions..."

sudo chown -R www-data:www-data storage bootstrap/cache
sudo chmod -R ug+rwX storage bootstrap/cache

if [[ -f storage/oauth-private.key ]]; then
    sudo chmod 600 storage/oauth-private.key
fi

if [[ -f storage/oauth-public.key ]]; then
    sudo chmod 600 storage/oauth-public.key
fi
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This also helps prevent another classic Laravel production error:

storage/logs/laravel.log: Permission denied
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Production automation should leave your application in a known-good state after every deployment.


The GPT Action OAuth Configuration

Once the backend architecture was ready, the GPT Action itself needed OAuth configuration.

Conceptually:

Authentication Type:
OAuth

Client ID:
<passport-client-id>

Client Secret:
<passport-client-secret>

Authorization URL:
https://auth.example.com/oauth/authorize

Token URL:
https://auth.example.com/oauth/token

Scopes:
profile channels.read posts.read posts.write
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ChatGPT provides a callback URL.

That callback must match the redirect URI registered with your OAuth server.

Exactly.

Not approximately.

Not "same domain."

Not "close enough."

Exactly.

If ChatGPT gives you:

https://chat.openai.com/aip/g-example/oauth/callback
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then your Passport OAuth client needs that callback.


Be Careful When Recreating or Editing Your GPT

During development, callback URLs can become a source of confusion.

If the callback associated with the GPT changes, your Passport client can still contain the old redirect URI.

Then ChatGPT sends:

redirect_uri = NEW_CALLBACK
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while Passport expects:

OLD_CALLBACK
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OAuth fails.

Instead of constantly creating new clients and secrets, we built tooling to safely update the existing Passport client's redirect URI while preserving:

Client ID
Secret
Grant Types
Name
State
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That proved extremely useful during development.

The broader lesson is:

Build diagnostic and administrative tools around OAuth instead of manually editing database rows.


Passport Schemas Change Between Versions

Another lesson: don't assume examples written for an older Laravel Passport version match your installation.

For example, older examples may reference:

redirect
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while newer Passport versions can use fields such as:

redirect_uris
grant_types
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If you run something like:

Laravel\Passport\Client::all([
    'id',
    'name',
    'redirect',
    'revoked'
]);
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against a schema that no longer contains redirect, you'll get a database error.

Always inspect the actual Passport version and schema you're using.

Don't blindly copy an OAuth tutorial written several major versions ago.


Build Diagnostic Artisan Commands

One of the best things we did during this project was build small Artisan commands specifically for OAuth diagnostics.

For example, a command could inspect:

Client ID
Client name
Redirect URIs
Grant types
Revoked state
Client type
Secret storage
Exact redirect match
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You can even securely prompt for the client secret and verify whether it matches the stored hash without printing either value.

Conceptually:

php artisan oauth:inspect-clients \
    'CLIENT_ID' \
    --redirect-uri='EXACT_CALLBACK' \
    --verify-secret
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Output might look like:

State: active
Client type: confidential
Secret storage: hashed
Grant types: authorization_code, refresh_token
Exact redirect match: yes
Submitted secret matches: yes
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That's dramatically better than guessing.


Your OpenAPI Schema Is the GPT's Map

Authentication gets the GPT through the front door.

Your OpenAPI specification tells it what it can actually do.

Suppose your application exposes:

/api/v1/connected-channels:
  get:
    operationId: getConnectedChannels
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And:

/api/v1/posts:
  post:
    operationId: createPost
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The descriptions matter.

Good:

summary: Get the authenticated user's connected social media channels
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Less useful:

summary: Get channels
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The model needs enough semantic information to understand when an operation applies.

Operation IDs should also be descriptive:

getConnectedChannels
createSocialPost
scheduleSocialPost
getScheduledPosts
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rather than:

get1
post2
action3
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Treat your OpenAPI specification as part API contract and part AI interface.


Confirmation Before Destructive or External Actions

AI-driven API access raises another UX consideration.

Some operations should happen immediately.

For example:

Show me my connected channels.

That's read-only.

But:

Publish this to Facebook and Instagram.

has an external side effect.

For workflows like publishing, deleting, sending, purchasing, or modifying important records, design your Action and GPT instructions so the user has an opportunity to confirm what will happen.

A good interaction might be:

User:
Create a post about our product launch for Facebook and Instagram.

GPT:
Here's the proposed post:

...

Would you like me to publish this to Facebook and Instagram?

User:
Yes.

GPT:
→ API Action
→ publish
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This is better than making every conversational request immediately destructive.


Test the Entire Chain, Not Just OAuth

An OAuth token successfully being issued does not mean your integration works.

We tested the entire path:

ChatGPT
    ↓
Authorization request
    ↓
Laravel Passport
    ↓
Authorization code
    ↓
Token exchange
    ↓
Access token
    ↓
GPT Action request
    ↓
Main Laravel API
    ↓
External token introspection
    ↓
Account mapping
    ↓
Scope validation
    ↓
Correct application user
    ↓
Actual application data
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The moment that mattered wasn't when Passport issued a token.

It was when we could ask:

Show me my connected social channels.

and receive the channels belonging to the correct application user.

That proved the architecture end-to-end.


Test With More Than One User

Before calling an OAuth integration production-ready, test user isolation.

Create or use at least two application users.

Then verify:

User A
→ OAuth
→ User A's resources
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and:

User B
→ OAuth
→ User B's resources
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Never:

User B
→ OAuth
→ User A's resources
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Also test:

  • Token refresh
  • Expired tokens
  • Revoked tokens
  • Missing scopes
  • Invalid scopes
  • Missing account mapping
  • Conflicting account mapping
  • Replayed handoff
  • Auth service unavailable
  • Invalid server-to-server secret
  • Invalid OAuth client secret
  • Incorrect redirect URI

Happy-path testing is not enough for authentication systems.


The ChatGPT Account Limitation You Need to Know About

Now for the frustrating part.

You can build the entire integration correctly and still discover that you cannot distribute your GPT the way you expected.

As of 2026, OpenAI's documentation states that new GPT creation and publishing are not available on personal ChatGPT accounts, including:

Free
Go
Plus
Pro
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Existing GPTs can remain available to their owners and can still be edited when the applicable plan and permissions allow it.

However, creating and publishing GPTs is currently available through eligible managed workspaces such as:

Business
Enterprise
Edu
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subject to workspace permissions.

This is important because upgrading from ChatGPT Plus to the much more expensive personal ChatGPT Pro plan does not necessarily solve the GPT publishing problem.

Pro is still a personal account.

If your goal is to create a GPT that customers can access, you need to evaluate the current Business/Enterprise/Edu workspace requirements before investing significant development time.


Why This Matters for Independent Developers and SaaS Companies

This creates an interesting situation for solo developers and small SaaS companies.

You may be able to:

  • Build the GPT
  • Configure the Action
  • Implement OAuth
  • Test the API
  • Use the GPT privately
  • Prove the entire architecture

but still need an eligible managed ChatGPT workspace before you can distribute that GPT to customers.

That doesn't make the development work useless.

Far from it.

Your OAuth-enabled API can potentially support many other clients.

And your private GPT can serve as a beta environment while you validate whether customers actually want conversational access to your application.

That's exactly how I would approach it.

Prove demand before adding another recurring expense.


A Private GPT Can Still Be a Valuable Beta

If you already have an existing GPT on a personal account, private testing can be extremely useful.

You can validate:

OAuth
Account linking
API authentication
Scopes
Token refresh
OpenAPI operations
Prompt behavior
Error handling
User confirmation
API response design
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before making the integration broadly available.

That gives you a working prototype.

If customers later start asking:

Can I control this from ChatGPT?

you already know the backend architecture works.

At that point, moving the GPT into an eligible managed workspace becomes a business decision rather than an experiment.


GPT Actions Are Really API Product Development

One of my biggest takeaways from this project is that GPT Actions aren't primarily about prompt engineering.

The hard part isn't writing:

You are a helpful social media assistant.
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The hard part is everything behind it:

Authentication
Authorization
OAuth
Account linking
Scopes
API design
OpenAPI
Security boundaries
Error handling
Deployment
User isolation
Token lifecycle
Observability
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In other words:

Building a serious GPT Action is backend application development.

If you already have a well-designed Laravel API, you're in a strong position.

If you don't have an API yet, adding GPT Actions may expose architectural work that needs to happen first.


Laravel Is a Great Fit for GPT Action Integrations

Laravel gives you many of the building blocks needed for this kind of project:

  • Routing
  • Middleware
  • Authentication
  • Authorization
  • Laravel Passport
  • HTTP client
  • Validation
  • Service containers
  • Queues
  • Events
  • Logging
  • Database transactions
  • Testing
  • Rate limiting
  • Configuration management

A typical architecture can remain very Laravel-native.

For example:

GPT Action
    ↓
Laravel API Route
    ↓
Authentication Middleware
    ↓
Scope Middleware
    ↓
Controller
    ↓
Service
    ↓
Application Logic
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You don't need to throw away your existing Laravel architecture just because AI is involved.


You Probably Don't Need to Rewrite Your Laravel Application for AI

This is another area where companies can easily overspend.

Adding AI functionality doesn't necessarily mean rewriting your application around AI.

If you already have a working Laravel application, you may only need:

API endpoints
OAuth
OpenAPI schema
Identity mapping
AI-specific service layer
Additional authorization
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Your existing:

Models
Services
Jobs
Queues
Database
Business logic
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can often remain exactly where they are.

The AI becomes another interface into the application.

That's a much more practical way to modernize an existing system.


Need GPT Actions Added to Your Laravel Application?

If you have an existing Laravel or custom PHP application and you're wondering:

Can ChatGPT securely interact with my application?

The answer may very well be yes.

At Custom PHP Design, we work with custom PHP and Laravel applications and can help design and implement integrations involving:

  • ChatGPT GPT Actions
  • OpenAI integrations
  • Laravel APIs
  • OpenAPI specifications
  • OAuth 2.0
  • Laravel Passport
  • API authentication
  • Account linking
  • External SaaS integrations
  • AI-assisted workflows
  • Existing application modernization
  • AWS deployments
  • CI/CD
  • Laravel architecture

Whether you have a modern Laravel application or a custom PHP system that's been evolving for years, you don't necessarily need to rebuild everything to take advantage of AI.

Sometimes the right solution is to build a secure bridge between what you already have and what AI can now provide.

👉 Learn more about Custom PHP Design:

Custom PHP Design

If you're trying to determine whether GPT Actions can be integrated into your existing Laravel application, Custom PHP Design can help evaluate the architecture and build the integration.


Final Architecture

After working through the authentication, account linking, API middleware, introspection, and deployment issues, the architecture ultimately looked like this:

┌─────────────────────────┐
│        ChatGPT          │
│       Custom GPT        │
└────────────┬────────────┘
             │
             │ OAuth Authorization
             ▼
┌─────────────────────────┐
│   Laravel Auth Service  │
│                         │
│   Laravel Passport      │
│   OAuth Clients         │
│   Access Tokens         │
│   Refresh Tokens        │
└────────────┬────────────┘
             │
             │ Account Mapping
             ▼
┌─────────────────────────┐
│  Application Identity   │
│                         │
│ Auth User ↔ App User    │
└────────────┬────────────┘
             │
             │ Token Introspection
             ▼
┌─────────────────────────┐
│ Main Laravel Application│
│                         │
│ API Authentication      │
│ OAuth Scope Validation  │
│ Existing Business Logic │
└────────────┬────────────┘
             │
             ▼
┌─────────────────────────┐
│      Customer Data      │
└─────────────────────────┘
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And from the user's perspective?

It can be as simple as:

Show me my connected social channels.

That's the part users see.

Everything else is our job as developers.


Final Thoughts

GPT Actions open up some genuinely interesting possibilities for existing Laravel applications.

But don't mistake them for a simple prompt-engineering exercise.

Once a GPT needs to securely access private customer data or perform actions on behalf of a user, you're dealing with traditional application engineering concerns:

Identity
Authentication
Authorization
OAuth
API security
User isolation
Scopes
Token management
Infrastructure
Deployment
Observability
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The good news is that Laravel is extremely well suited to solving those problems.

And once the foundation exists, the conversational layer can be surprisingly powerful.

A user doesn't necessarily need to know which API endpoint to call.

They don't need to know your JSON structure.

They don't need to know your controller names.

They can simply explain what they want.

ChatGPT determines the appropriate Action.

Your Laravel application remains responsible for determining whether that action is authorized and executing it safely.

That's the architecture I expect we'll see more of as AI becomes another interface for traditional web applications.


Want to Add ChatGPT Actions to Laravel?

If you have a Laravel or custom PHP application and want to explore secure ChatGPT integration, OAuth, APIs, or AI-driven workflows, visit:

Custom PHP Design

https://www.customphpdesign.com/

We specialize in custom PHP and Laravel development, including integrations that connect existing applications with modern APIs, cloud infrastructure, and AI platforms.

Instead of replacing years of existing development, we can help determine how to extend what you already have.

Laravel + APIs + OAuth + GPT Actions can turn an existing application into something your users can interact with conversationally.

And that's a pretty exciting direction for custom web development.


This article is based on lessons learned while implementing and debugging a real Laravel-to-ChatGPT OAuth integration. Always review the latest OpenAI GPT and Actions documentation before implementing your own integration, as account availability, publishing requirements, OAuth behavior, and platform features can change.

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