# Send HL7 Message

> Perform Send HL7 Message through HL7.

Source: [https://genhealth.ai/docs/workflows/integrations/hl7/hl7_send_message](https://genhealth.ai/docs/workflows/integrations/hl7/hl7_send_message)

Integration: [HL7](https://genhealth.ai/docs/workflows/integrations/hl7.md)

- Handler: `hl7_send_message`

- Connection type: `hl7_mllp`

## Use in a workflow

Copy this discovered node config, fill params from the input contract, and validate the complete graph. Integration results are available as {{node_id.default.field}}. Check business success before dependent writes; completion alone does not prove business success.

```json

{
  "_group": "HL7",
  "params": {
    "wait_for_ack": true,
    "ack_timeout_seconds": 30
  },
  "handler": "hl7_send_message"
}

```

[Action contracts](https://genhealth.ai/docs/workflows/action-contracts.md) · [Run recovery](https://genhealth.ai/docs/workflows/operations.md)

## Inputs

- `message` — Message (expression, required)
  Required literal value or workflow expression.
- `wait_for_ack` — Wait For Ack (boolean)
  Optional true-or-false value.
  Default: `true`
- `ack_timeout_seconds` — Ack Timeout Seconds (number)
  Optional numeric value.
  Default: `30`

## Outputs

- `success` — Success
- `ack_code` — Ack Code
- `ack_text` — Ack Text
- `control_id` — Control Id
- `acknowledged` — Acknowledged
- `failure_category` — Failure Category
- `error` — Error
- `error_type` — Error Type

Output schema completeness: `best_effort_declared`

## Safety

- External effect: `write`
- Confirmation recommended: no
- Retry safe: no
- Dry run supported: no

## Schemas

These schemas are first-pass authoring guidance. Runtime validation remains authoritative.

### Input schema

```json
{
  "type": "object",
  "required": [
    "message"
  ],
  "properties": {
    "message": {
      "description": "Required literal value or workflow expression.",
      "x-workflow-field-type": "expression"
    },
    "wait_for_ack": {
      "type": "boolean",
      "default": true,
      "description": "Optional true-or-false value.",
      "x-workflow-field-type": "boolean"
    },
    "ack_timeout_seconds": {
      "type": "number",
      "default": 30,
      "description": "Optional numeric value.",
      "x-workflow-field-type": "number"
    }
  },
  "additionalProperties": false
}
```

### Output schema

```json
{
  "type": "object",
  "properties": {
    "error": {},
    "success": {},
    "ack_code": {},
    "ack_text": {},
    "control_id": {},
    "error_type": {},
    "acknowledged": {},
    "failure_category": {}
  },
  "additionalProperties": true
}
```