Errors and what to do

Your app's API answers errors as JSON with a numeric code and a message:

{ "code": 101, "error": "Object not found." }

The SDKs turn it into a Parse.Error with code and message. Check the code, not the text: messages can change between Parse Server versions.

try {
  await query.get(id);
} catch (e) {
  if (e.code === Parse.Error.OBJECT_NOT_FOUND) { /* gone, or not yours */ }
  else if (e.code === Parse.Error.INVALID_SESSION_TOKEN) { await Parse.User.logOut(); /* log in again */ }
  else throw e;
}

The ones you'll meet

Code	Name	Usually means	What to do
101	OBJECT_NOT_FOUND	The object doesn't exist, or the user may not read it (ACL). Also wrong username or password at login	Check the ACL and who is logged in
119	OPERATION_FORBIDDEN	A class-level permission refuses the operation, or it needs the master key	Check the class's CLP, or do it in a cloud function
141	SCRIPT_FAILED	A cloud function or trigger threw an error	The message is the thrown error; see Core › Logs
142	VALIDATION_ERROR	A trigger refused the object	Show the message to the user
209	INVALID_SESSION_TOKEN	The session expired or was revoked (e.g. password change)	Log the user out and in again
206	SESSION_MISSING	The operation needs a logged-in user	Log in first
202 / 203	USERNAME_TAKEN / EMAIL_TAKEN	Sign-up with an existing username or email	Ask for another, or offer login
205	EMAIL_NOT_FOUND	Password reset or verification for an unknown email
137	DUPLICATE_VALUE	A unique index refused a value
111	INCORRECT_TYPE	A field got a value of another type than its schema	Fix the value, or the schema
105	INVALID_KEY_NAME	A field name isn't allowed (e.g. starts with $)	Rename the field
102	INVALID_QUERY	The query is malformed, or uses an operator the version doesn't support	Check the query

Parse's full list of codes has the rest.

Without a code

Answer	Means	What to do
403 {"error": "unauthorized"}	Wrong Application ID or client key, or a key the app doesn't accept	Copy the keys again from App Settings › Security & Keys
403 {"error": "unauthorized: master key is required"}	The operation needs the master key	Do it in cloud code or with an access token
502, 503	The app is starting or restarting, e.g. during a deployment	Retry with a backoff; check Runtime › Deployments
No answer after 60 seconds	The request ran past the time limit	Make it smaller, add an index, or move the work to a job

Errors from cloud code

What you throw is what the client gets. Throw a Parse.Error with a fitting code, so clients can handle it:

throw new Parse.Error(Parse.Error.VALIDATION_ERROR, 'A title is required.');

Anything else thrown (a bug, a failed call to another service) reaches the client as 141 SCRIPT_FAILED with its message, and is logged in Core › Logs. Don't put secrets in error messages: the client sees them.

The Management API

The API used with access tokens has its own error format and codes (300 to 305 for tokens and the proxy): see Errors in the API reference.

Find the cause faster

• Core › Logs shows each cloud code error with its stack trace.
• Through MCP, *"show me the errors from the last hour and find the code that throws them"* reads the logs and the cloud code together.