> For the complete documentation index, see [llms.txt](https://docs.openalgo.in/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.openalgo.in/api-documentation/v1/orders-api/modifygttorder.md).

# ModifyGttOrder

Modify an active GTT trigger. The body is a **full replacement** of the trigger spec — same shape as `PlaceGTTOrder` plus `trigger_id`. The broker's underlying PUT replaces trigger prices, leg limits, and order params atomically.

> **Send everything you want to keep.** Modify is not a patch — fields you omit are not preserved.

## SINGLE vs OCO — Same Trigger Type as Original

You can modify any of the price levels, the quantity, or the pricetype, but you **cannot switch a SINGLE into an OCO** (or vice versa). If you need that, cancel and re-place.

| Type                        | Use when…                               | Triggers | Orders fired                         |
| --------------------------- | --------------------------------------- | -------- | ------------------------------------ |
| **SINGLE**                  | You set up one entry/exit at a level.   | 1        | 1                                    |
| **OCO** (One-Cancels-Other) | You set up a stoploss + target bracket. | 2        | 1 of 2 (the other is auto-cancelled) |

> In SINGLE there is no second leg and no automatic cancel — once your one trigger fires and the order is placed, the GTT is finished.

## How to Choose `triggerprice_sl` vs `triggerprice_tg` (SINGLE only)

For SINGLE, exactly **one** of these two fields is your trigger price; set the other to `0`. Pick based on **where your trigger sits relative to LTP**:

| Field             | Trigger sits…         | Typical intent                                |
| ----------------- | --------------------- | --------------------------------------------- |
| `triggerprice_sl` | **below** current LTP | SELL stop-loss · BUY-on-dip · BUY-the-fall    |
| `triggerprice_tg` | **above** current LTP | BUY breakout · SELL-at-target · SELL-the-rise |

For OCO, you always send **both**: `triggerprice_sl` (the lower trigger, your stoploss) **and** `triggerprice_tg` (the higher trigger, your target).

> **Note on naming.** In **SINGLE**, `triggerprice_sl` / `triggerprice_tg` are just *the trigger price* — the generic "price at which the order is triggered". The `_sl` / `_tg` suffix is only a directional hint (sits below / above LTP); SINGLE has no stoploss leg. In **OCO**, the suffix becomes a real role: `triggerprice_sl` is the **stoploss-leg trigger** and `triggerprice_tg` is the **target-leg trigger**.

## Endpoint URL

```http
Local Host   :  POST http://127.0.0.1:5000/api/v1/modifygttorder
Ngrok Domain :  POST https://<your-ngrok-domain>.ngrok-free.app/api/v1/modifygttorder
Custom Domain:  POST https://<your-custom-domain>/api/v1/modifygttorder
```

## Sample API Request — SINGLE: "Move my IDEA dip-buy from 9.55 → 9.65, raise limit to 9.60"

```json
{
  "apikey": "<your_app_apikey>",
  "strategy": "My GTT Strategy",
  "trigger_id": "23132604291205",
  "trigger_type": "SINGLE",
  "exchange": "NSE",
  "symbol": "IDEA",
  "action": "BUY",
  "product": "CNC",
  "quantity": 1,
  "pricetype": "LIMIT",
  "price": 9.60,
  "triggerprice_sl": 9.65,
  "triggerprice_tg": 0,
  "stoploss": null,
  "target": null
}
```

LTP is currently above 9.65 → trigger sits **below** LTP → use `triggerprice_sl`.

## Sample cURL Request

```bash
curl -X POST http://127.0.0.1:5000/api/v1/modifygttorder \
  -H 'Content-Type: application/json' \
  -d '{
  "apikey": "<your_app_apikey>",
  "strategy": "My GTT Strategy",
  "trigger_id": "23132604291205",
  "trigger_type": "SINGLE",
  "exchange": "NSE",
  "symbol": "IDEA",
  "action": "BUY",
  "product": "CNC",
  "quantity": 1,
  "pricetype": "LIMIT",
  "price": 9.60,
  "triggerprice_sl": 9.65,
  "triggerprice_tg": 0,
  "stoploss": null,
  "target": null
}'
```

## Sample API Response

```json
{
  "status": "success",
  "trigger_id": "23132604291205"
}
```

## Sample API Request — OCO: "Tighten my INFY bracket — stop 1480→1485, target 1620→1625"

```json
{
  "apikey": "<your_app_apikey>",
  "strategy": "Bracket OCO",
  "trigger_id": "23132604291213",
  "trigger_type": "OCO",
  "exchange": "NSE",
  "symbol": "INFY",
  "action": "SELL",
  "product": "CNC",
  "quantity": 5,
  "pricetype": "LIMIT",
  "price": 0,
  "triggerprice_sl": 1485,
  "stoploss": 1483,
  "triggerprice_tg": 1625,
  "target": 1627
}
```

`price=0` because OCO uses per-leg limit prices: `stoploss` (the SL leg's limit) and `target` (the target leg's limit).

## Parameters Description

| Parameters       | Description                                                                                                                   | Mandatory/Optional | Default Value |
| ---------------- | ----------------------------------------------------------------------------------------------------------------------------- | ------------------ | ------------- |
| apikey           | OpenAlgo API key (string)                                                                                                     | Mandatory          | -             |
| strategy         | Strategy identifier (string)                                                                                                  | Mandatory          | -             |
| trigger\_id      | The trigger ID returned by `PlaceGTTOrder` — identifies which active GTT to modify (string)                                   | Mandatory          | -             |
| trigger\_type    | `SINGLE` or `OCO` — must match the original trigger's type (string)                                                           | Mandatory          | -             |
| exchange         | NSE, BSE, NFO, BFO, CDS, BCD, MCX (string)                                                                                    | Mandatory          | -             |
| symbol           | Trading symbol in OpenAlgo format (string)                                                                                    | Mandatory          | -             |
| action           | `BUY` or `SELL` (string). For OCO, applies to both legs.                                                                      | Mandatory          | -             |
| product          | `CNC` (equity delivery) or `NRML` (F\&O overnight). MIS is **not** supported for GTT. (string)                                | Mandatory          | -             |
| quantity         | New order quantity. Integer for equity/F\&O; fractional float allowed for crypto (number).                                    | Mandatory          | -             |
| pricetype        | `LIMIT` or `MARKET` (string)                                                                                                  | Optional           | `LIMIT`       |
| price            | **SINGLE only** — new limit price of the child order. Send `0` when `pricetype=MARKET`. Ignored for OCO. (float)              | Mandatory          | -             |
| triggerprice\_sl | New trigger price below LTP. **SINGLE**: use this OR `triggerprice_tg`. **OCO**: required (the stoploss-leg trigger). (float) | Conditional        | `0`           |
| triggerprice\_tg | New trigger price above LTP. **SINGLE**: use this OR `triggerprice_sl`. **OCO**: required (the target-leg trigger). (float)   | Conditional        | `0`           |
| stoploss         | **OCO only** — new limit price for the stoploss leg's child order. Ignored for SINGLE. (float, `null`, or `""`)               | Conditional        | `null`        |
| target           | **OCO only** — new limit price for the target leg's child order. Ignored for SINGLE. (float, `null`, or `""`)                 | Conditional        | `null`        |

### Trigger Field Rules

| trigger\_type | What you must send                                                            | Constraint                                                                            |
| ------------- | ----------------------------------------------------------------------------- | ------------------------------------------------------------------------------------- |
| `SINGLE`      | exactly one of `triggerprice_sl` / `triggerprice_tg` (>0); the other = `0`    | `price` is the child order's limit; send `0` for MARKET.                              |
| `OCO`         | all four: `triggerprice_sl`, `stoploss`, `triggerprice_tg`, `target` (all >0) | `triggerprice_sl < triggerprice_tg`. Both legs share `action`, `quantity`, `product`. |

## Response Fields

| Field       | Type   | Description                               |
| ----------- | ------ | ----------------------------------------- |
| status      | string | `"success"` or `"error"`                  |
| trigger\_id | string | Modified trigger ID (same value you sent) |
| message     | string | Error message (on failure)                |

## What Can Be Modified?

| Parameter                                              | Modifiable | Notes                                                 |
| ------------------------------------------------------ | ---------- | ----------------------------------------------------- |
| Trigger prices (`triggerprice_sl` / `triggerprice_tg`) | Yes        | For OCO, both legs swap atomically.                   |
| Limit prices (`price` / `stoploss` / `target`)         | Yes        |                                                       |
| `quantity`                                             | Yes        | Must be a valid lot size for F\&O.                    |
| `pricetype`                                            | Yes        | `LIMIT` ↔ `MARKET` (see broker-specific notes below). |
| `trigger_type`                                         | No         | Cannot switch SINGLE ↔ OCO — cancel and re-place.     |
| `symbol` / `exchange`                                  | No         | Cannot change instrument.                             |
| `action`                                               | No         | Cannot change BUY ↔ SELL.                             |

## Notes

* Numeric fields (`quantity`, `price`, `triggerprice_sl`, `triggerprice_tg`, `stoploss`, `target`) are JSON floats. Empty strings (`""`) for `stoploss`/`target`/`triggerprice_sl`/`triggerprice_tg` are also accepted and coerced to `null`/`0`.
* **Modify is a full replacement** — every field on the trigger is replaced. Always send all fields you want to keep, not just the diff.
* **Only active GTTs can be modified.** Triggered, cancelled, or expired GTTs are immutable.
* **`last_price` is fetched server-side** from the broker's quotes endpoint. You don't need to send it.
* **OCO modify atomicity**: OpenAlgo aims to update both legs of an OCO atomically; some brokers expose a per-leg modify under the hood and may, in rare failure cases, leave the OCO in a half-modified state — re-issue the modify or cancel and re-place if the response indicates partial failure.
* **MARKET handling**: same auto-conversion behaviour as [PlaceGTTOrder](/api-documentation/v1/orders-api/placegttorder.md#notes) — broker-specific quirks are absorbed in the broker layer.
* **Semi-auto mode** blocks GTT modify (parity with `ModifyOrder`) — switch to Auto mode if you see a 403.

## Error Scenarios

| Error                                                                             | Cause                                         |
| --------------------------------------------------------------------------------- | --------------------------------------------- |
| `trigger_id is required` (400)                                                    | Missing `trigger_id`                          |
| `Modify GTT order is not allowed in Semi-Auto mode` (403)                         | User in Semi-Auto mode                        |
| `triggerprice_sl: Stoploss trigger must be less than target trigger`              | OCO with `triggerprice_sl >= triggerprice_tg` |
| `GTT supports only CNC (delivery) or NRML (overnight F&O); MIS is intraday-only.` | `product=MIS` submitted                       |
| `Failed to fetch last_price from broker quotes` (502)                             | Broker quotes endpoint unavailable            |
| `Sandbox GTT support not yet implemented` (501)                                   | Analyzer mode is enabled                      |
| `GTT orders are not supported for broker 'X' yet` (501)                           | Broker capability gate                        |

***

**Back to**: [API Documentation](/api-documentation/v1.md)