# Reassign API

> Build on Reassign, the 24-hour day planner. Read and change a day plan with the REST API, or connect an AI assistant through the MCP server.

Source: https://reassign.dev/

Reassign is a 24-hour circular day planner. Use the Reassign API to read a day plan and to add, change, and remove its events.

New to Reassign? [Learn what Reassign is](https://reassign.ai).

[Quickstart](https://reassign.dev/quickstart.md)

[Authentication](https://reassign.dev/authentication.md)

**MCP server URL**

```text
https://reassign.app/api/mcp
```

**Claude Code**

```bash
claude mcp add --transport http reassign https://reassign.app/api/mcp
```

## Two ways to build

|             | REST API v1                                              | MCP server                                                     |
| ----------- | -------------------------------------------------------- | -------------------------------------------------------------- |
| Use it for  | Your own scripts, tools, and apps                        | An AI assistant that supports the Model Context Protocol (MCP) |
| Address     | `https://reassign.app/api/v1`                            | `https://reassign.app/api/mcp`                                 |
| Credentials | A personal access token or an OAuth 2.0 access token     | An OAuth 2.0 access token only                                 |
| Format      | JSON over HTTP                                           | Streamable HTTP, in stateless JSON mode                        |
| Guide       | [Authentication](https://reassign.dev/authentication.md) | [Connect an AI assistant](https://reassign.dev/mcp.md)         |

- Both use the same two scopes: `events:read` and `events:write`.
- Most calls need Reassign Pro. The 7-day free trial includes it. `GET /api/v1/me` works on all plans.
- Times are local datetimes, `"YYYY-MM-DDTHH:MM"`, on a 24-hour clock. Dates are `"YYYY-MM-DD"`. Both are in the time zone of the account.

Read [Core concepts](https://reassign.dev/concepts.md) for the model of a day plan.

## Getting started

Create a personal access token in the Reassign app. Then make your first request to the REST API. The [Quickstart](https://reassign.dev/quickstart.md) shows each step, from the token to a new event.

[Make your first request](https://reassign.dev/quickstart.md)

[Get a token](https://reassign.dev/authentication.md)

## Guides

- [Quickstart](https://reassign.dev/quickstart.md): Create a personal access token, make your first request to the Reassign REST API, read a day, and add an event.
- [Authentication](https://reassign.dev/authentication.md): Authenticate your requests to the Reassign REST API with a personal access token or with OAuth 2.0.
- [Connect an AI assistant](https://reassign.dev/mcp.md): Connect an AI assistant to the Reassign MCP server. The assistant can then read and change your day plan.
- [Core concepts](https://reassign.dev/concepts.md): The model behind the Reassign API: the day plan, local datetimes and spans, names and formats, validation, recurring events, categories, projects and priority, checklists, focus intervals, change polls, the Inbox, trackers, reviews, calendars, undo, and scopes.
- [Errors](https://reassign.dev/errors.md): The error format of the Reassign REST API, the error codes, rejected batches, the rate limits, and how to handle errors.
- [Changelog](https://reassign.dev/changelog.md): Changes to the Reassign API and to its documentation.

## API reference

- [Account](https://reassign.dev/reference/account.md): Read the identity, the plan, and the scopes of the token that calls the Reassign REST API.
- [Events](https://reassign.dev/reference/events.md): Poll, read, search, create, change, and delete events on the Reassign 24-hour planner with the REST API.
- [Scheduling](https://reassign.dev/reference/scheduling.md): Read days, find free time, book work into it, and undo changes with the Reassign REST API.
- [Categories](https://reassign.dev/reference/categories.md): Read, create, update, and delete the areas, activity types, and projects of a Reassign account.
- [Backlog](https://reassign.dev/reference/backlog.md): Read and change the Inbox of a Reassign account: capture blocks, schedule them on a day, and move events back.
- [Moments & trackers](https://reassign.dev/reference/moments-and-trackers.md): Define trackers, then log, read, edit, and delete moments with the Reassign REST API.
- [Day reviews](https://reassign.dev/reference/day-reviews.md): Record how a past day went, then confirm or discard the review of that day with the Reassign REST API.
- [Energy & weather](https://reassign.dev/reference/energy-and-weather.md): Read the forecast energy curve and the weather report for a day. Both endpoints return a short text report.
- [Calendars](https://reassign.dev/reference/calendars.md): List the calendars and task lists from the connected sources of the user. Use the ids to sync events.
- [Quick command (AI)](https://reassign.dev/reference/command.md): Send one line or a braindump of free text. An AI model turns it into events, Inbox blocks, and logged moments, and applies them.