---
title: "Add Watchlist Item"
method: POST
path: "/v1/watchlists/{watchlist_id}/items"
tags: ["Watchlist"]
---

# Add Watchlist Item

`POST /v1/watchlists/{watchlist_id}/items`

## Request

- Base URL: `https://api.clearstreet.com`
- URL: `https://api.clearstreet.com/v1/watchlists/{watchlist_id}/items`
- Auth: HTTP bearer

Add an instrument to a watchlist

## Path parameters

- `watchlist_id` string, uuid, required

## Request body

- AddWatchlistItemRequest: Request to add an instrument to a watchlist
  - `instrument_id` string, required: Instrument identifier: either an instrument UUID or a symbol (symbol for equities, OSI for options). Non-UUID inputs are resolved server-side.

## Response `200`

Item added successfully

- object
  - `error` ApiError: A direct mapping of tonic::Status, for use in HTTP responses.
    - `code` integer, required: The error code is used to identify the nature of the error. It corresponds to an HTTP status code.
    - `details` object[]
    - `message` string, required: A human-readable message providing more details about the error.
  - `metadata` ResponseMetadata, required: Metadata for the response. This will always contain a request ID which can be used to identify the request to Clear Street for tracing, and optionally may include pagination data.
    - `next_page_token` string, byte, nullable: Base64URL-encoded pagination token
    - `page_number` integer, nullable: Pagination. Included if this was a GET (list) response
    - `previous_page_token` string, byte, nullable: Base64URL-encoded pagination token
    - `request_id` string, required: A unique ID for this request, generated upon ingestion of the request.
    - `total_items` integer, nullable: Total number of items available (not just in this page).
    - `total_pages` integer, nullable: Total number of pages available.
  - `data` AddWatchlistItemData, required: Response data for adding a watchlist item
    - `item_id` string, uuid, required: ID of the created item

## Other responses

- `400`: Invalid request or watchlist is full
- `404`: Watchlist or instrument not found
- `409`: Instrument already exists in watchlist
- `500`: Internal server error

## Changes

- **2026-10-16** `1bd9eddeffc8`: 3 breaking
  - the `instrument_id` request property's minLength was increased from `0` to `1`
  - removed `subschema #1, subschema #2` from the `instrument_id` request property `oneOf` list
  - the `instrument_id` request property type changed from no type to `string`
- **2026-06-08** `920881a98f6c`: 1 breaking, 1 info
  - removed `subschema #1, subschema #2` from the `instrument_id` request property `oneOf` list
  - added `subschema #1, subschema #2` to the `instrument_id` request property `oneOf` list

[Operation history](https://skmtc.dev/clear-street/apis/clear-street-trading-api/changes/v1/watchlists/:watchlist_id/items/post.md)

---

[API](https://skmtc.dev/clear-street/apis/clear-street-trading-api.md) - [All operations](https://skmtc.dev/clear-street/apis/clear-street-trading-api/llms.txt) - [OpenAPI document](https://skmtc.dev/clear-street/apis/clear-street-trading-api/revisions/52e77ea7d731?raw)