## TL;DR

A required field was left empty. The error names the field: populate it (or give it a default) and retry.

## Error

```text
REQUIRED_FIELD_MISSING: Required fields are missing: [AccountNumber]
```

## Steps

1. Read the error for the missing field name Expected: you know what is required.
2. Populate the field in your payload Expected: it has a value.
3. Or set a default on the field if it is always the same Expected: future records are fine.
4. Re-run the operation Expected: it succeeds.

## When to use

- REQUIRED_FIELD_MISSING
- A required field is empty

## When not to use

- The field has a value (then check for whitespace-only strings)
- The requirement comes from a validation rule (then read the rule)

## Tool compatibility

- Salesforce required fields
- Data loader inserts

## Variant phrasings

### required field missing salesforce

The error names the field. Populate it and retry.

### REQUIRED_FIELD_MISSING

Same: fill the named field or set a default.

## Why it happens

Page layouts and API requirements differ: a field optional in the UI can be required by automation. Agents fill what the UI shows.

## Edge cases

- Universally required fields (like Name) cannot be made optional
- Record types can change which fields are required

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_NjKfr4sv_IpayQRstURvsg