| name | generate-frontend-forms |
| description | Guide for creating forms using Sentry's new form system. Use when implementing forms, form fields, validation, or auto-save functionality. |
Form System Guide
This skill provides patterns for building forms using Sentry's new form system built on TanStack React Form and Zod validation.
Core Principle
-
Always use the new form system (useScrapsForm, AutoSaveForm) for new forms. Never create new forms with the legacy JsonForm or Reflux-based systems.
-
All forms should be schema based. DO NOT create a form without schema validation.
Imports
All form components are exported from @sentry/scraps/form:
import {z} from 'zod';
import {
AutoSaveForm,
defaultFormOptions,
setFieldErrors,
useScrapsForm,
} from '@sentry/scraps/form';
Important: DO NOT import from deeper paths, like '@sentry/scraps/form/field'. You can only use what is part of the PUBLIC interface in the index file in @sentry/scraps/form.
Form Hook: useScrapsForm
The main hook for creating forms with validation and submission handling.
Basic Usage
import {z} from 'zod';
import {defaultFormOptions, useScrapsForm} from '@sentry/scraps/form';
const schema = z.object({
email: z.string().email('Invalid email'),
name: z.string().min(2, 'Name must be at least 2 characters'),
});
function MyForm() {
const form = useScrapsForm({
...defaultFormOptions,
defaultValues: {
email: '',
name: '',
},
validators: {
onDynamic: schema,
},
onSubmit: ({value, formApi}) => {
console.log(value);
},
});
return (
<form.AppForm form={form}>
<form.AppField name="email">
{field => (
<field.Layout.Stack label="Email" required>
<field.Input value={field.state.value} onChange={field.handleChange} />
</field.Layout.Stack>
)}
</form.AppField>
<form.SubmitButton>Submit</form.SubmitButton>
</form.AppForm>
);
}
Important: Always spread defaultFormOptions first. It configures validation to run on submit initially, then on every change after the first submission. This is why validators are defined as onDynamic, and it's what provides a consistent UX.
Returned Properties
| Property | Description |
|---|
AppForm | Root wrapper component (provides form context and renders <form> element). Must receive form={form} prop. |
AppField | Field renderer component |
FieldGroup | Section grouping with title |
SubmitButton | Pre-wired submit button |
Subscribe | Subscribe to form state changes |
reset() | Reset form to default values |
handleSubmit() | Manually trigger submission |
Field Components
All fields are accessed via the field render prop and follow consistent patterns.
Input Field (Text)
<form.AppField name="firstName">
{field => (
<field.Layout.Stack label="First Name" required>
<field.Input
value={field.state.value}
onChange={field.handleChange}
placeholder="Enter your name"
/>
</field.Layout.Stack>
)}
</form.AppField>
Number Field
<form.AppField name="age">
{field => (
<field.Layout.Stack label="Age" required>
<field.Number
value={field.state.value}
onChange={field.handleChange}
min={0}
max={120}
step={1}
/>
</field.Layout.Stack>
)}
</form.AppField>
Select Field (Single)
<form.AppField name="country">
{field => (
<field.Layout.Stack label="Country">
<field.Select
value={field.state.value}
onChange={field.handleChange}
options={[
{value: 'us', label: 'United States'},
{value: 'uk', label: 'United Kingdom'},
]}
/>
</field.Layout.Stack>
)}
</form.AppField>
Select Field (Multiple)
<form.AppField name="tags">
{field => (
<field.Layout.Stack label="Tags">
<field.Select
multiple
value={field.state.value}
onChange={field.handleChange}
options={[
{value: 'bug', label: 'Bug'},
{value: 'feature', label: 'Feature'},
]}
clearable
/>
</field.Layout.Stack>
)}
</form.AppField>
Switch Field (Boolean)
<form.AppField name="notifications">
{field => (
<field.Layout.Stack label="Enable notifications">
<field.Switch checked={field.state.value} onChange={field.handleChange} />
</field.Layout.Stack>
)}
</form.AppField>
TextArea Field
<form.AppField name="bio">
{field => (
<field.Layout.Stack label="Bio">
<field.TextArea
value={field.state.value}
onChange={field.handleChange}
rows={4}
placeholder="Tell us about yourself"
/>
</field.Layout.Stack>
)}
</form.AppField>
Range Field (Slider)
<form.AppField name="volume">
{field => (
<field.Layout.Stack label="Volume">
<field.Range
value={field.state.value}
onChange={field.handleChange}
min={0}
max={100}
step={10}
/>
</field.Layout.Stack>
)}
</form.AppField>
Radio Field
Radio fields use a composable API with Radio.Group and Radio.Item. Radio.Group provides group context that changes how the label is rendered for proper accessibility semantics.
Important: The layout (and its label) must be rendered inside Radio.Group. The group context is provided by Radio.Group, so placing the layout outside will result in incorrect accessibility semantics.
<form.AppField name="priority">
{field => (
<field.Radio.Group value={field.state.value} onChange={field.handleChange}>
<field.Layout.Stack label="Priority">
<field.Radio.Item value="low">Low</field.Radio.Item>
<field.Radio.Item value="medium">Medium</field.Radio.Item>
<field.Radio.Item value="high" description="Urgent issues">
High
</field.Radio.Item>
</field.Layout.Stack>
</field.Radio.Group>
)}
</form.AppField>
For horizontal arrangement of radio items, use a Flex or Stack wrapper inside the layout:
import {Flex} from '@sentry/scraps/layout';
<field.Radio.Group value={field.state.value} onChange={field.handleChange}>
<field.Layout.Row label="Priority">
<Flex gap="lg">
<field.Radio.Item value="low">Low</field.Radio.Item>
<field.Radio.Item value="high">High</field.Radio.Item>
</Flex>
</field.Layout.Row>
</field.Radio.Group>;
Custom Fields with BaseField
For one-off fields that don't have a built-in component (e.g. a color picker, or any custom input), use field.Base. It provides a render prop with all the necessary accessibility and form integration props (ref, disabled, aria-invalid, aria-describedby, onBlur, name, id) that you spread onto your native element.
<form.AppField name="color">
{field => (
<field.Layout.Row label="Brand Color">
<field.Base<HTMLInputElement>>
{(baseProps, {indicator}) => (
<Flex flexGrow={1}>
<input
{...baseProps}
type="color"
value={field.state.value}
onChange={e => field.handleChange(e.target.value)}
/>
{indicator}
</Flex>
)}
</field.Base>
</field.Layout.Row>
)}
</form.AppField>
The render prop receives two arguments:
baseProps — accessibility and form integration props (ref, disabled, aria-invalid, aria-describedby, onBlur, name, id) to spread onto your element
{indicator} — the auto-save status indicator (spinner/checkmark) as a React node, which you can place wherever makes sense in your custom layout
The element type is inferred from the passed ref, so if you don't pass one, you have to manually annotate it with <field.Base<HTMLInputElement>>.
field.Base automatically handles:
- Merging refs (for scroll-to-hash and external ref forwarding)
- Disabling the field when auto-save is pending
- Setting
aria-invalid based on validation state
- Linking to hint text via
aria-describedby
Use field.Base instead of building custom wrappers that duplicate this logic. It works with any native HTML element or third-party component that accepts standard props.
Layouts
Two layout options are available for positioning labels and fields.
Stack Layout (Vertical)
Label above, field below. Best for forms with longer labels or mobile layouts.
<field.Layout.Stack
label="Email Address"
hintText="We'll never share your email"
required
>
<field.Input value={field.state.value} onChange={field.handleChange} />
</field.Layout.Stack>
Row Layout (Horizontal)
Label on left (~50%), field on right. Compact layout for settings pages.
<field.Layout.Row label="Email Address" hintText="We'll never share your email" required>
<field.Input value={field.state.value} onChange={field.handleChange} />
</field.Layout.Row>
Compact Variant
Both Stack and Row layouts support a variant="compact" prop. In compact mode, the hint text appears as a tooltip on the label instead of being displayed below. This saves vertical space while still providing the hint information.
<field.Layout.Row label="Email" hintText="We'll never share your email">
<field.Input ... />
</field.Layout.Row>
<field.Layout.Row label="Email" hintText="We'll never share your email" variant="compact">
<field.Input ... />
</field.Layout.Row>
<field.Layout.Stack label="Email" hintText="We'll never share your email" variant="compact">
<field.Input ... />
</field.Layout.Stack>
When to Use Compact:
- Settings pages with many fields where vertical space is limited
- Forms where hint text is supplementary, not essential
- Dashboards or panels with constrained height
Custom Layouts
You are allowed to create new layouts if necessary, or not use any layouts at all. Without a layout, you should render field.meta.Label and optionally field.meta.HintText for a11y.
<form.AppField name="firstName">
{field => (
<Flex gap="md">
<field.Meta.Label required>First Name:</field.Meta.Label>
<field.Input value={field.state.value ?? ''} onChange={field.handleChange} />
</Flex>
)}
</form.AppField>
Layout Props
| Prop | Type | Description |
|---|
label | string | Field label text |
hintText | string | Helper text (below label by default, tooltip in compact mode) |
required | boolean | Shows required indicator |
variant | "compact" | Shows hint text in tooltip instead of below label |
Field Groups
Group related fields into sections with a title.
<form.FieldGroup title="Personal Information">
<form.AppField name="firstName">{/* ... */}</form.AppField>
<form.AppField name="lastName">{/* ... */}</form.AppField>
</form.FieldGroup>
<form.FieldGroup title="Contact Information">
<form.AppField name="email">{/* ... */}</form.AppField>
<form.AppField name="phone">{/* ... */}</form.AppField>
</form.FieldGroup>
Disabled State
Fields accept disabled as a boolean or string. When a string is provided, it displays as a tooltip explaining why the field is disabled.
<field.Input disabled value={field.state.value} onChange={field.handleChange} />
<field.Input
disabled="This feature requires a Business plan"
value={field.state.value}
onChange={field.handleChange}
/>
Validation with Zod
Schema Definition
import {z} from 'zod';
const userSchema = z.object({
email: z.string().email('Please enter a valid email'),
password: z.string().min(8, 'Password must be at least 8 characters'),
age: z.number().gte(13, 'You must be at least 13 years old'),
bio: z.string().optional(),
tags: z.array(z.string()).optional(),
address: z.object({
street: z.string().min(1, 'Street is required'),
city: z.string().min(1, 'City is required'),
}),
});
Nullable Fields with Refine
When a field starts as null (e.g., a required select with no initial selection), use .nullable().refine() in the schema. This creates a difference between the schema's input type (which accepts null) and its output type (which does not). To handle this correctly:
- Type
defaultValues explicitly as z.input<typeof schema> — this allows null as an initial value.
- Call
schema.parse(value) inside onSubmit to narrow from z.input to z.output, stripping the null before passing to your mutation.
const schema = z.object({
provider: z
.enum(['GitHub', 'LaunchDarkly'])
.nullable()
.refine(v => v !== null, 'Provider is required'),
name: z.string().min(1, 'Name is required'),
});
const defaultValues: z.input<typeof schema> = {
provider: null,
name: '',
};
type FormOutput = z.output<typeof schema>;
const form = useScrapsForm({
...defaultFormOptions,
defaultValues,
validators: {onDynamic: schema},
onSubmit: ({value}) => {
return mutation.mutateAsync(schema.parse(value)).catch(() => {});
},
});
Important: Do NOT use non-null assertions (value.provider!) or type casts to work around nullable fields. The schema.parse() approach is both type-safe and validates at runtime.
Conditional Validation
Use .refine() for cross-field validation:
const schema = z
.object({
password: z.string(),
confirmPassword: z.string(),
})
.refine(data => data.password === data.confirmPassword, {
message: 'Passwords do not match',
path: ['confirmPassword'],
});
Conditional Fields
Use form.Subscribe to show/hide fields based on other field values:
<form.Subscribe selector={state => state.values.plan === 'enterprise'}>
{showBilling =>
showBilling ? (
<form.AppField name="billingEmail">
{field => (
<field.Layout.Stack label="Billing Email" required>
<field.Input value={field.state.value} onChange={field.handleChange} />
</field.Layout.Stack>
)}
</form.AppField>
) : null
}
</form.Subscribe>
Error Handling
Server-Side Errors
Use setFieldErrors to display backend validation errors:
import {useMutation} from '@tanstack/react-query';
import {setFieldErrors} from '@sentry/scraps/form';
import {fetchMutation} from 'sentry/utils/queryClient';
function MyForm() {
const mutation = useMutation({
mutationFn: (data: {email: string; username: string}) => {
return fetchMutation({
url: '/users/',
method: 'POST',
data,
});
},
});
const form = useScrapsForm({
...defaultFormOptions,
defaultValues: {email: '', username: ''},
validators: {onDynamic: schema},
onSubmit: async ({value, formApi}) => {
try {
await mutation.mutateAsync(value);
} catch (error) {
setFieldErrors(formApi, {
email: {message: 'This email is already registered'},
username: {message: 'Username is taken'},
});
}
},
});
}
Important: setFieldErrors supports nested paths with dot notation: 'address.city': {message: 'City not found'}
Error Display
Validation errors automatically show as a warning icon with tooltip in the field's trailing area. No additional code needed.
Auto-Save Pattern
For settings pages where each field saves independently, use AutoSaveForm.
Basic Auto-Save Form
import {z} from 'zod';
import {AutoSaveForm} from '@sentry/scraps/form';
import {fetchMutation} from 'sentry/utils/queryClient';
const schema = z.object({
displayName: z.string().min(1, 'Display name is required'),
});
function SettingsForm() {
return (
<AutoSaveForm
name="displayName"
schema={schema}
initialValue={user.displayName}
mutationOptions={{
mutationFn: data => {
return fetchMutation({
url: '/user/',
method: 'PUT',
data,
});
},
onSuccess: data => {
// Update React Query cache
queryClient.setQueryData(['user'], old => ({...old, ...data}));
},
}}
>
{field => (
<field.Layout.Row label="Display Name">
<field.Input value={field.state.value} onChange={field.handleChange} />
</field.Layout.Row>
)}
</AutoSaveForm>
);
}
Auto-Save Behavior by Field Type
| Field Type | When it saves |
|---|
| Input, TextArea | On blur (when user leaves field) |
| Select (single) | Immediately when selection changes |
| Select (multiple) | When menu closes, or when X/clear clicked while menu closed |
| Switch | Immediately when toggled |
| Radio | Immediately when selection changes |
| Range | When user releases the slider, or immediately with keyboard |
Auto-Save Status Indicators
The form system automatically shows:
- Spinner while saving (pending)
- Checkmark on success (fades after 2s)
- Warning icon on validation error (with tooltip)
Important: Do NOT use toasts to communicate auto-save status. The built-in inline indicators (spinner, checkmark, warning icon) are the correct feedback mechanism. Toasts are noisy and disruptive for fields that save frequently on every change.
Confirmation Dialogs
For dangerous operations (security settings, permissions), use the confirm prop to show a confirmation modal before saving. The confirm prop accepts either a string or a function.
<AutoSaveForm
name="require2FA"
schema={schema}
initialValue={false}
confirm={value =>
value
? 'This will remove all members without 2FA. Continue?'
: 'Are you sure you want to allow members without 2FA?'
}
mutationOptions={{...}}
>
{field => (
<field.Layout.Row label="Require Two-Factor Auth">
<field.Switch checked={field.state.value} onChange={field.handleChange} />
</field.Layout.Row>
)}
</AutoSaveForm>
Confirm Config Options:
| Type | Description |
|---|
string | Always show this message before saving |
(value) => string | undefined | Function that returns a message based on the new value, or undefined to skip confirmation |
Note: Confirmation dialogs always focus the Cancel button for safety, preventing accidental confirmation of dangerous operations.
Examples:
confirm="Are you sure you want to change this setting?"
confirm={value => value ? 'Are you sure you want to enable this?' : undefined}
confirm={value => !value ? 'Disabling this removes security protection.' : undefined}
confirm={value =>
value
? 'Enable 2FA requirement for all members?'
: 'Allow members without 2FA?'
}
confirm={value => value === 'delete' ? 'This will permanently delete all data!' : undefined}
Form Submission
Important: Always use TanStack Query mutations (useMutation) for form submissions. This ensures proper loading states, error handling, and cache management.
Using Mutations
import {useMutation} from '@tanstack/react-query';
import {fetchMutation} from 'sentry/utils/queryClient';
function MyForm() {
const mutation = useMutation({
mutationFn: (data: FormData) => {
return fetchMutation({
url: '/endpoint/',
method: 'POST',
data,
});
},
onSuccess: () => {
},
});
const form = useScrapsForm({
...defaultFormOptions,
defaultValues: {...},
validators: {onDynamic: schema},
onSubmit: ({value}) => {
return mutation.mutateAsync(value).catch(() => {});
},
});
}
Resetting After Save
When a form stays on the page after submission (e.g., settings pages), call form.reset() after a successful mutation. This re-syncs the form with updated defaultValues so it becomes pristine again — any UI that depends on the form being dirty (like conditionally shown Save/Cancel buttons) will update correctly.
onSubmit: ({value}) =>
mutation
.mutateAsync(value)
.then(() => form.reset())
.catch(() => {}),
Note: AutoSaveForm handles this automatically. You only need to add this when using useScrapsForm.
Submit Button
<Flex gap="md" justify="end">
<form.ResetButton>Reset</form.ResetButton>
<form.SubmitButton>Save Changes</form.SubmitButton>
</Flex>
The SubmitButton automatically:
- Disables while submission is pending
- Triggers form validation before submit
Do's and Don'ts
Form System Choice
<JsonForm fields={[{name: 'email', type: 'text'}]} />;
const form = useScrapsForm({
...defaultFormOptions,
defaultValues: {email: ''},
validators: {onDynamic: schema},
});
Default Options
const form = useScrapsForm({
defaultValues: {name: ''},
});
const form = useScrapsForm({
...defaultFormOptions,
defaultValues: {name: ''},
});
Nullable Default Values
onSubmit: ({value}) => {
return mutation.mutateAsync({...value, provider: value.provider!});
};
const form = useScrapsForm({
...defaultFormOptions,
defaultValues: {provider: null, name: ''},
});
const defaultValues: z.input<typeof schema> = {provider: null, name: ''};
const form = useScrapsForm({
...defaultFormOptions,
defaultValues,
validators: {onDynamic: schema},
onSubmit: ({value}) => {
return mutation.mutateAsync(schema.parse(value)).catch(() => {});
},
});
Form Submissions
onSubmit: async ({value}) => {
await api.post('/users', value);
};
onSubmit: ({value}) => {
return mutation.mutateAsync(value);
};
const mutation = useMutation({
mutationFn: data => fetchMutation({url: '/users/', method: 'POST', data}),
});
onSubmit: ({value}) => {
return mutation
.mutateAsync(value)
.then(() => form.reset())
.catch(() => {});
};
Field Value Handling
<field.Input value={field.state.value} />
<field.Input value={field.state.value ?? ''} />
Validation Messages
z.string().min(1);
z.string().min(1, 'Email address is required');
Auto-Save Feedback
mutationOptions={{
mutationFn: (data) => fetchMutation({url: '/user/', method: 'PUT', data}),
onSuccess: () => {
addSuccessMessage('Saved!');
},
}}
mutationOptions={{
mutationFn: (data) => fetchMutation({url: '/user/', method: 'PUT', data}),
onSuccess: (data) => {
queryClient.setQueryData(['user'], old => ({...old, ...data}));
},
}}
Auto-Save Cache Updates
Always update the data store or cache in onSuccess. Without this, toggling a field back to its original value won't trigger a save — TanStack Form compares against defaultValues (derived from initialValue) and skips submission when the value matches.
mutationOptions={{
mutationFn: (data) => fetchMutation({url: '/user/', method: 'PUT', data}),
}}
mutationOptions={{
mutationFn: (data) => fetchMutation({url: '/user/', method: 'PUT', data}),
onSuccess: (data) => {
queryClient.setQueryData(['user'], old => ({...old, ...data}));
},
}}
Auto-Save Mutation Typing
Type the mutationFn with the API's data type, not the zod schema type. The schema is for client-side field validation — the mutation should accept whatever the API endpoint accepts. Don't use generic types like Record<string, unknown> either, as that breaks TanStack Form's ability to narrow field types.
NEVER pass call-site generics to mutationOptions, useMutation, or any TanStack Query function. Types must be inferred, not asserted. See the full rules in static/AGENTS.md under "TanStack Query Type Inference."
mutationOptions<unknown, RequestError, Variables, Context>({...})
useMutation<Response, RequestError, Variables>({...})
const opts = mutationOptions({
mutationFn: (data: Record<string, unknown>) => fetchMutation({...}),
});
const opts = mutationOptions({
mutationFn: (data: Partial<z.infer<typeof preferencesSchema>>) => fetchMutation({...}),
});
type MyContext = {previousData: UserDetails};
const opts = mutationOptions({
mutationFn: (data: Partial<UserDetails>) =>
fetchMutation<UserDetails>({...}),
});
Make sure the zod schema's types are compatible with the API type. For example, if the API expects a string union like 'off' | 'low' | 'high', use z.enum(['off', 'low', 'high']) instead of z.string().
Form Reset After Save
onSubmit: ({value}) => {
return mutation.mutateAsync(value).catch(() => {});
};
onSubmit: ({value}) => {
return mutation
.mutateAsync(value)
.then(() => form.reset())
.catch(() => {});
};
Layout Choice
<field.Layout.Row label="Please enter the primary email address for your account">
<field.Layout.Stack label="Please enter the primary email address for your account">
Quick Reference Checklist
When creating a new form:
When creating auto-save fields:
File References
| File | Purpose |
|---|
static/app/components/core/form/scrapsForm.tsx | Main form hook |
static/app/components/core/form/autoSaveForm.tsx | Auto-save wrapper |
static/app/components/core/form/field/*.tsx | Individual field components |
static/app/components/core/form/layout/index.tsx | Layout components |
static/app/components/core/form/form.stories.tsx | Usage examples |