Connect Salesforce through an External Client App and a dedicated integration user. Sim supports client credentials and JWT bearer authentication; API calls use the selected integration user's profile and permission sets.
An API-only integration user cannot complete interactive OAuth. Both server-to-server flows support that user type.
Sim supports both server-to-server flows. Pick one:
| Feature | Client credentials | JWT bearer |
|---|---|---|
| What Sim stores | Consumer key + consumer secret | Consumer key + private key |
| Who calls run as | The app's Run As user | The username you name in Sim |
| Salesforce setup | Enable Client Credentials Flow, set Run As | Upload a certificate, pre-authorize the user |
| Pick it when | You want the simplest setup | Your security policy forbids shared secrets, or you want one app to serve several integration users |
Both flows authenticate the Salesforce tools as an integration user. The user's license and permissions determine which operations can succeed.
Prerequisites
You need a Salesforce admin to create the External Client App and the integration user. Every API call Sim makes runs with the integration user's permissions, so plan that user's profile and permission sets deliberately.
Set up the External Client App
1. Create a dedicated integration user
In Salesforce, go to Setup → Users → New User. Set License to Salesforce Integration (an API-only license, where available in your org) and Profile to Minimum Access - API Only Integrations
Create a permission set backed by the Salesforce API Integration permission set license, grant it the object and field permissions your workflows need (least privilege), and assign it to the user
If your org doesn't have Salesforce Integration licenses, any standard user with the API Enabled permission works too — but a dedicated API-only user keeps the credential's access explicit and auditable.
2. Create the External Client App
External Client Apps are Salesforce's current-generation connected apps and the default way to create new OAuth apps.
Go to Setup → External Client App Manager → New External Client App, give the app a name and contact email, and keep it local to your org (not packaged for distribution)
Open the app's Edit Settings → API (Enable OAuth Settings) section and turn on Enable OAuth
Enter any placeholder Callback URL (e.g. https://login.salesforce.com/services/oauth2/callback) — it's required by the form but unused by this flow
Add the OAuth scopes Manage user data via APIs (api) and Access unique user identifiers (openid) — api is required for the flow, and openid lets Sim look up the integration user's name via the userinfo endpoint (the instance URL comes back in the token response itself)
Client credentials only: enable the Client Credentials Flow in the OAuth settings and acknowledge the warning. Skip this if you're setting up JWT bearer — that flow has its own toggle (see below)
Create the app
3. Configure the Run As user
Open your app in External Client App Manager and edit its Policies
Under OAuth Policies → Client Credentials Flow, set Run As to the integration user from step 1, then save. That page holds only the Run As picker — the Enable Client Credentials Flow checkbox itself lives in Edit Settings → OAuth Settings, where you set it in step 2
Every API call Sim makes executes with this user's permissions.
4. Copy the consumer key and secret
Open the app's Settings → OAuth Settings and click Consumer Key and Secret (Salesforce prompts for identity verification). Copy the Consumer Key and Consumer Secret.
The Consumer Secret plus the Run As configuration is full API access as the integration user. Treat both values like passwords — do not commit them to source control or share them publicly. Sim encrypts them at rest.
Use an existing Connected App
Creating new Connected Apps is blocked by default: Salesforce restricted creation as of Spring '26 — re-enabling it requires a request to Salesforce Support. Use an External Client App for new setups.
If you already have a classic Connected App, it keeps working and the credential fields are identical — the token endpoint and Sim configuration don't change. Configure it the classic way:
In Setup → App Manager, confirm the app has Enable OAuth Settings, the Manage user data via APIs (api) and Access unique user identifiers (openid) scopes, and Enable Client Credentials Flow checked
From App Manager, open the app's Manage page, click Edit Policies, and set Run As under Client Credentials Flow to your integration user. Permitted Users policies don't apply to the Client Credentials Flow's execution user, so no pre-authorization is needed
Open the app with View and click Manage Consumer Details to copy the Consumer Key and Consumer Secret
Use JWT bearer authentication
The JWT Bearer Flow authenticates with an uploaded certificate rather than a shared secret, and runs as a username you name in Sim rather than the app's Run As user. Set this up instead of steps 3 and 4 above. Create the integration user and app as above, skipping the Client Credentials Flow toggle. Then configure JWT bearer below and find the My Domain host in step 5.
Generate a key pair. server.key stays with Sim; server.crt is uploaded to Salesforce:
openssl req -x509 -sha256 -nodes -days 3650 -newkey rsa:2048 \
-keyout server.key -out server.crt -subj "/CN=sim-salesforce"Keep server.key somewhere safe — Sim stores it encrypted and never shows it again.
Salesforce requires an RSA key of at least 2048 bits for this flow; an ECDSA key is rejected. The uploaded certificate must also stay under 4 KB, which a 2048-bit self-signed cert comfortably is.
In External Client App Manager → your app → Edit Settings → OAuth Settings, turn on Enable OAuth (the JWT toggle does not appear until it is on), then Enable JWT Bearer Flow, and use Upload Files to upload server.crt. On a legacy Connected App the equivalent is Use digital signatures with the same file
Edit the app's Policies → OAuth Policies and set Permitted Users to Admin approved users are pre-authorized
This step is mandatory. The JWT flow requires prior approval of the app, and an API-only integration user can never grant that approval interactively — there is no UI for them to log in to. Without pre-authorization every token request fails with user hasn't approved this consumer.
Assign the integration user's profile or a permission set to the app, so that user is covered by the pre-authorization
Assign it through the profile, or through a second permission set that does not carry the Salesforce API Integration permission set license. A permission set backed by that license cannot hold an Assigned Connected Apps / Assigned External Client Apps section at all, so the app can never be assigned from the same permission set that grants the user its object access. Getting this wrong produces exactly the user hasn't approved this consumer failure this step exists to prevent.
Copy the Consumer Key as in step 4. There is no consumer secret to copy — the JWT flow doesn't use one
5. Find your My Domain host
Go to Setup and search for My Domain. The host is required — Salesforce rejects the Client Credentials Flow at login.salesforce.com and test.salesforce.com. Depending on your org type it looks like:
- Production:
yourorg.my.salesforce.com - Sandbox:
yourorg--sandboxname.sandbox.my.salesforce.com - Developer Edition:
yourorg.develop.my.salesforce.com(Salesforce appends-dev-edonly when it generated the name for you)
Sim also accepts other partitioned My Domain hosts (scratch, demo, patch, trailblaze, free).
Use the my.salesforce.com host, not the my.salesforce-setup.com host you see in the address bar while working in Setup, and not lightning.force.com. Government Cloud Plus domains (*.my.salesforce.mil) are not currently supported.
Permissions and license limits
There's no scope picking beyond the api and openid scopes on the app — what the credential can actually do is the integration user's profile plus permission sets. In particular:
- Object and field access for every object your workflows read or write, plus API Enabled
- Customize Application for tools that manage custom fields and custom objects (Tooling API) — a Minimum Access API-only user passes validation but fails these specific tools without it
- Run Reports and folder access for report and dashboard tools
A permissions gap surfaces at run time as a Salesforce API error; fix it on the integration user's permission sets — no changes are needed in Sim.
On the Salesforce Integration (API-only) license specifically, SOQL and CRUD on standard objects are well supported, but two areas are not safe to assume:
- Reports and dashboards are unverified on this license. Salesforce documents neither a grant nor a prohibition. Test them in a sandbox before depending on them, and remember the user also needs access to the report or dashboard folder.
- Apex-related access requires separate verification. Do not assume this license or its permission-set license can grant the Apex Class Access required by an operation. Custom field and object tools have their own Customize Application requirement.
If a workflow must run reports, verify them with the intended license in a sandbox, or use a standard-seat integration user with the required report and folder access.
Add the integration user app to Sim
Open Integrations from your workspace sidebar
Search for "Salesforce" and open it, then click Add to Sim and choose Add integration user app
In the Add Salesforce integration user app dialog, pick the Authentication method you configured. The dialog then asks only for that flow's fields:
- Client credentials — Consumer key and Consumer secret
- JWT bearer — Consumer key, the Private key (paste the whole
server.keyfile,-----BEGINline included), and the Run as username (the integration user's Salesforce username, e.g.integration.user@yourorg.com)
Then paste your My Domain host (e.g. yourorg.my.salesforce.com) and optionally set a display name and description
Click Add integration user app. Sim verifies the credentials by minting a real access token against your My Domain host. A host that doesn't resolve gets its own error message; every other misconfiguration surfaces as a general authentication error — re-check the values and the app's OAuth policies.
Use the credential in workflows
Add a Salesforce block to your workflow. In the credential dropdown, select the saved Salesforce integration user app. Configure the selected operation.
The block calls your org's REST API with a freshly minted access token — the same requests as the OAuth flow, with access governed by the integration user's license and permissions.
Token behavior
Neither flow returns a refresh token or expires_in. Opaque access-token lifetime follows Salesforce session policy; the documented default is two hours, with settings from 15 minutes to 24 hours. Sim caches tokens conservatively for at most 10 minutes and mints replacements. JWT-format access tokens can carry an exp claim that shortens that cache window. Connection or token failures can still stop a workflow.
Deactivating or freezing the integration user — the Run As user for client credentials, or the run-as username for JWT bearer — stops all token minting with an invalid_grant error, halting every workflow that uses the credential. Password policies that expire the user's API access have the same effect. Treat the integration user as production infrastructure.
Troubleshooting and rotation
| Problem | What to check |
|---|---|
JWT: user hasn't approved this consumer | Set Permitted Users to Admin approved users are pre-authorized and assign the run-as user's profile or permitted permission set to the app. An API-only user cannot grant interactive approval. |
JWT: app_not_found or audience error | Use the My Domain host for the org containing the app and that app's consumer key. |
| JWT: invalid assertion or signature | Upload the certificate that matches the private key in Sim. Confirm that you pasted the private key rather than server.crt. |
| Passphrase-protected key | Sim has no passphrase field. Decrypt it first with openssl rsa -in server.pass.key -out server.key. PKCS#1 (BEGIN RSA PRIVATE KEY) and PKCS#8 (BEGIN PRIVATE KEY) PEM containers are accepted. |
| Client credentials: authentication rejected | Enable the flow in the app's settings and configure an active Run As user in its policies. Check the consumer key and secret. |
| A tool fails after connection succeeds | Grant the integration user the needed object/field permissions, Customize Application for schema tools, or Run Reports plus folder access for reports. |
| The integration user is frozen or deactivated | Reactivate it or choose an active integration user. Change the app's Run As policy for client credentials; for JWT, reconnect with the new username and pre-authorize that user. |
For client credentials, rotate the consumer secret in the app's OAuth settings (Consumer Key and Secret, or Manage Consumer Details for a legacy app). For JWT bearer, generate a matching key/certificate pair and replace the uploaded certificate and stored private key together. In Sim, open the saved credential under Integrations, select Reconnect, and restate the authentication method and required fields. Stored secrets are not returned to populate the dialog.
See Salesforce's External Client App setup and OAuth app guidance.