> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chamelio.ai/llms.txt
> Use this file to discover all available pages before exploring further.
# Add Task Attachments
> Upload files to a task and record them on its activity log
## Endpoint
```
POST /tasks/{task_id}/attachments
```
## Authentication
This endpoint requires authentication via API key. Include your API key in the `X-API-Key` header:
```bash theme={null}
X-API-Key: ca_your_api_key_here
```
## Path Parameters
| Parameter | Type | Required | Description |
| --------- | ------- | -------- | --------------------------------- |
| `task_id` | integer | Yes | ID of the task to attach files to |
## Request Body
All fields are optional, but a request that supplies neither `files` nor `attachment_ids` records nothing.
| Field | Type | Required | Description |
| ---------------- | ------------------------- | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `files` | array | No | Files to upload and attach. Defaults to an empty list. See [File Object](#file-object) below |
| `attach_to_task` | boolean | No | When `true`, the files are stored on the task itself as well as recorded on the activity log. When `false` they are recorded on the activity log only. Defaults to `false` |
| `attachment_ids` | array of integers or null | No | IDs of attachments that already exist on the task. Used when `attach_to_task` is `false` to reference them from the new activity log entry. Defaults to `null` |
| `reply_to` | integer or null | No | ID of an activity log entry this attachment is a reply to. Defaults to `null` |
| `user_email` | string or null | No | Email of the user to attribute the upload to. Defaults to the API key's owner |
### File Object
| Field | Type | Required | Description |
| ---------------- | ------ | -------- | ------------------------------------------------------------------------------------------------ |
| `filename` | string | Yes | Filename including its extension (e.g. `"amendment.pdf"`). The extension is read from this value |
| `base64_content` | string | Yes | Base64-encoded file content |
## Request Example
```bash cURL theme={null}
curl -X POST "https://platform.chamelio.ai/tasks/12345/attachments" \
-H "X-API-Key: ca_your_api_key_here" \
-H "Content-Type: application/json" \
-d '{
"files": [
{
"filename": "counterparty-redlines.pdf",
"base64_content": "JVBERi0xLjQKJeLjz9MK..."
}
],
"attach_to_task": true
}'
```
```python Python theme={null}
import base64
import requests
task_id = 12345
with open("counterparty-redlines.pdf", "rb") as f:
content = base64.b64encode(f.read()).decode()
url = f"https://platform.chamelio.ai/tasks/{task_id}/attachments"
headers = {
"X-API-Key": "ca_your_api_key_here",
"Content-Type": "application/json"
}
payload = {
"files": [
{
"filename": "counterparty-redlines.pdf",
"base64_content": content
}
],
"attach_to_task": True
}
response = requests.post(url, headers=headers, json=payload)
print(response.json())
```
```javascript JavaScript theme={null}
const taskId = 12345;
const response = await fetch(
`https://platform.chamelio.ai/tasks/${taskId}/attachments`,
{
method: 'POST',
headers: {
'X-API-Key': 'ca_your_api_key_here',
'Content-Type': 'application/json'
},
body: JSON.stringify({
files: [
{
filename: 'counterparty-redlines.pdf',
base64_content: 'JVBERi0xLjQKJeLjz9MK...'
}
],
attach_to_task: true
})
}
);
const data = await response.json();
console.log(data);
```
## Response
### Success Response
**Status Code:** `200 OK`
```json theme={null}
{
"attachment_ids": [8821, 8822]
}
```
### Response Fields
| Field | Type | Description |
| ---------------- | ----------------- | ---------------------------------------------------------------------------- |
| `attachment_ids` | array of integers | IDs of the attachments that were added, in the order the files were supplied |
## Error Responses
### 401 Unauthorized
Returned when authentication fails. See the [authentication errors](/api-reference/api-keys#authentication-errors) section for details.
```json theme={null}
{
"detail": "Invalid API key"
}
```
### 404 Not Found
Returned when no task exists with the given ID.
```json theme={null}
{
"detail": "Not found"
}
```
### 422 Unprocessable Entity
Returned when the request body fails validation, for example a file missing its `base64_content`.
```json theme={null}
{
"detail": [
{
"loc": ["body", "files", 0, "base64_content"],
"msg": "Field required",
"type": "missing"
}
]
}
```
### 500 Internal Server Error
Returned when the request fails due to a server error.
```json theme={null}
{
"detail": "Failed to add task attachments"
}
```
## Notes
The upload is attributed to the API key's owner unless you pass `user_email`, in which case it is
attributed to that user. Use [`POST /v2/tasks/{task_id}/attachments`](/api-reference/endpoint/v2/tasks/attachments)
if you want the acting user taken from an OAuth token instead.
`attach_to_task` controls where the files land. With `false` (the default) they are uploaded and
referenced from a new activity log entry, leaving the task's own file list untouched. With `true`
they are additionally stored on the task, so they appear in [List Task Files](/api-reference/endpoint/tasks/list-files).
Pass `reply_to` with the ID of an existing activity log entry to thread the attachment underneath it,
for example when responding to a counterparty email already recorded on the task. Entry IDs come from
[Get Activity Logs](/api-reference/endpoint/tasks/activity-logs).
To reference files already on the task from a new activity log entry without re-uploading them, send
their `attachment_ids` with `attach_to_task` set to `false`.
## Use Cases
This endpoint is useful for:
* **Email ingestion** - Attach documents received from a counterparty to the task they belong to
* **Supporting documentation** - Add approvals, quotes, or certificates alongside a contract under review
* **Threaded correspondence** - Use `reply_to` to keep an exchange and its attachments together on the activity log