## Cancel Position Instruction

`client.V1.Positions.CancelPositionInstruction(ctx, instructionID, body) (*V1PositionCancelPositionInstructionResponse, error)`

**delete** `/v1/accounts/{account_id}/positions/instructions/{instruction_id}`

Cancel an outstanding position instruction by its server-assigned `id`.
Returns the updated instruction with status `CANCEL_REQUESTED`. The
terminal `CANCELLED` or `CANCEL_FAILED` state arrives asynchronously and
is observable via subsequent GETs.

### Parameters

- `instructionID string`

- `body V1PositionCancelPositionInstructionParams`

  - `AccountID param.Field[int64]`

    Account identifier

### Returns

- `type V1PositionCancelPositionInstructionResponse struct{…}`

  - `Data PositionInstruction`

    A position instruction and its current lifecycle state.

    - `ID string`

      Server-assigned id. Used as the path parameter on cancel.

    - `AccountID int64`

      Account the instruction belongs to.

    - `InstructionID string`

      Caller-supplied idempotency key echoed from the submit request; the
      server-assigned fallback when none was supplied.

    - `InstructionType PositionInstructionType`

      The action this instruction requests.

      - `const PositionInstructionTypeExercise PositionInstructionType = "EXERCISE"`

      - `const PositionInstructionTypeDoNotExercise PositionInstructionType = "DO_NOT_EXERCISE"`

      - `const PositionInstructionTypeContraryExercise PositionInstructionType = "CONTRARY_EXERCISE"`

    - `InstrumentID string`

      Identifier of the options contract this instruction acts on.

    - `Quantity string`

      Number of contracts included in the instruction.

    - `Status PositionInstructionStatus`

      Current lifecycle status.

      - `const PositionInstructionStatusSent PositionInstructionStatus = "SENT"`

      - `const PositionInstructionStatusAccepted PositionInstructionStatus = "ACCEPTED"`

      - `const PositionInstructionStatusRejected PositionInstructionStatus = "REJECTED"`

      - `const PositionInstructionStatusEngineRejected PositionInstructionStatus = "ENGINE_REJECTED"`

      - `const PositionInstructionStatusCancelRequested PositionInstructionStatus = "CANCEL_REQUESTED"`

      - `const PositionInstructionStatusCancelled PositionInstructionStatus = "CANCELLED"`

      - `const PositionInstructionStatusCancelFailed PositionInstructionStatus = "CANCEL_FAILED"`

      - `const PositionInstructionStatusUnknown PositionInstructionStatus = "UNKNOWN"`

    - `Symbol string`

      Options symbol (OSI) for display.

    - `AcceptedQuantity string`

      Number of contracts accepted by the clearing venue. Populated once
      the instruction reaches `ACCEPTED`.

    - `CreatedAt Time`

      When the instruction was first accepted by the service.

    - `RejectionReason string`

      Human-readable explanation populated on any non-success terminal
      status — `REJECTED`, `ENGINE_REJECTED`, or `CANCEL_FAILED`. On a
      `207 Multi-Status` batch submit the top-level `error` field
      summarizes the batch; per-row detail continues to live here.

    - `UpdatedAt Time`

      When the instruction's lifecycle state last changed.

### Example

```go
package main

import (
  "context"
  "fmt"

  "github.com/clear-street/clear-street-go"
  "github.com/clear-street/clear-street-go/option"
)

func main() {
  client := clearstreet.NewClient(
    option.WithAPIKey("My API Key"),
  )
  response, err := client.V1.Positions.CancelPositionInstruction(
    context.TODO(),
    "182bd5e5-6e1a-4fe4-a799-aa6d9a6ab26e",
    clearstreet.V1PositionCancelPositionInstructionParams{
      AccountID: 0,
    },
  )
  if err != nil {
    panic(err.Error())
  }
  fmt.Printf("%+v\n", response)
}
```

#### Response

```json
{
  "metadata": {
    "request_id": "request_id",
    "next_page_token": "U3RhaW5sZXNzIHJvY2tz",
    "page_number": 0,
    "previous_page_token": "U3RhaW5sZXNzIHJvY2tz",
    "total_items": 0,
    "total_pages": 0
  },
  "error": {
    "code": 400,
    "message": "Order quantity must be greater than zero",
    "details": [
      {
        "foo": "bar"
      }
    ]
  },
  "data": {
    "id": "0195f6d0-a1b2-7c3d-8e4f-5a6b7c8d9e02",
    "account_id": 122503,
    "instruction_id": "ui-20260424-001",
    "instruction_type": "EXERCISE",
    "instrument_id": "0195f6d0-a1b2-7c3d-8e4f-5a6b7c8d9e02",
    "quantity": "1",
    "status": "SENT",
    "symbol": "AAPL  280121C00195000",
    "accepted_quantity": null,
    "created_at": "2026-04-24T14:30:00Z",
    "rejection_reason": null,
    "updated_at": "2026-04-24T14:30:00Z"
  }
}
```