React Hook Form + Zod

1. Inspect the existing form contract

Read repository instructions, package manifest and lockfile, existing form components, and the submit endpoint. Identify installed React Hook Form, Zod, resolver, and UI component versions before selecting APIs. Use the repository's package manager and compatible dependencies; do not replace versions just because an example uses a different one.

Determine raw input types, parsed output, defaults, field lifecycle, server request format, and error response shape. Keep validation and payload changes within the requested scope.

2. Implement the smallest matching pattern

For a basic form, use the complete form template and its shared schema. Adapt the endpoint to the real application contract. The server validation template shows the matching request and validation response; connect authentication, authorization, and persistence through the real endpoint.

• Use register for native inputs. For controlled widgets, map value, change/blur handlers, name, and ref to the component's actual API. Spread field only when those props match; do not register the same field twice.
• Supply suitable defaults, especially avoiding undefined for controlled values. For data loaded after initialization, use the project's reset/values strategy and preserve dirty edits where required.
• When schema input and output differ, use useForm<z.input<typeof schema>, Context, z.output<typeof schema>>. z.infer represents output, so it is insufficient as the sole input type for transforms.
• Validate untrusted requests at the server boundary. Share a schema when raw input contracts match; if the client sends transformed output, validate that wire format with an appropriate server schema rather than accidentally transforming twice.
• Associate labels and error descriptions with inputs. Use explicit button types, prevent duplicate submits while pending, and expose recoverable failures.

Read advanced patterns only for multi-step forms, arrays, controlled widgets, transformations, async validation, or performance work.