---
title: "Add a field"
description: "Adds a field to a table."
canonical: "https://gtable.app/docs/builder-api/fields/create"
updated: "2026-10-05"
---

# Add a field

`POST https://studio.gtable.app/v1/apps/{appId}/tables/{tableId}/fields`

Adds a field to a table.

Leave `id` out: the platform mints an opaque `fld_…` and returns it. Every type carries its own `config`, and sending one that does not belong to the type is a validation error rather than a key nothing reads, call `fields.types` for the shapes. A computed field (lookup, rollup, formula, button) gets no column: it is derived at read time. A `link` creates its mirror field on the other table in the same write, and the two are deleted together.

Requires the `schema:write` scope. Operation `fields.create`. MCP tool `fields_create`. CLI, once published: `gtable fields create`.

## Path parameters

| Name      | Type   | Required | Description |
| --------- | ------ | -------- | ----------- |
| `appId`   | string | yes      |             |
| `tableId` | string | yes      |             |

## Headers

| Name              | Type   | Required | Description                                                                                                                                                                                                                                                        |
| ----------------- | ------ | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `Idempotency-Key` | string | no       | Any unique string. Sending the same key with the same request again returns the first response (marked `Idempotency-Replayed: true`) instead of running it twice. Reusing it for a different request is refused with 409. Kept for 24 hours. Up to 255 characters. |

## Request body

A object.