> For the complete documentation index, see [llms.txt](https://developers.felt.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.felt.com/rest-api/working-with-annotations.md).

# Working with annotations

{% hint style="info" %}

#### Note: Annotations were previously referred to as Elements.

References have been updated in the app and documentation, while REST API endpoint and JS SDK method naming remain unchanged.
{% endhint %}

Annotations sit on top of all data layers on a map. They are usually drawn in the Felt app, but can also be created and updated via the API.

{% hint style="info" %}
Combining annotations with [webhooks](/rest-api/listening-to-updates-using-webhooks.md) is a great way to create interactive data apps in Felt.
{% endhint %}

## Listing all annotations on a map

Annotations are returned as a [GeoJSON Feature Collection](https://geojson.org/).

{% tabs %}
{% tab title="curl" %}

```bash
# Your API token and map ID should look like this:
# FELT_API_TOKEN="felt_pat_ABCDEFUDQPAGGNBmX40YNhkCRvvLI3f8/BCwD/g8"
# MAP_ID="CjU1CMJPTAGofjOK3ICf1D"
FELT_API_TOKEN="<YOUR_API_TOKEN>"
MAP_ID="<YOUR_MAP_ID>"

curl \
  -H "Authorization: Bearer ${FELT_API_TOKEN}" \
  "https://felt.com/api/v2/maps/${MAP_ID}/elements"
```

{% endtab %}

{% tab title="Python" %}

```python
import requests

# Your API token and map ID should look like this:
# api_token = "felt_pat_ABCDEFUDQPAGGNBmX40YNhkCRvvLI3f8/BCwD/g8"
api_token = "<YOUR_API_TOKEN>"
map_id = "<YOUR_MAP_ID>"

r = requests.get(
  f"https://felt.com/api/v2/maps/{map_id}/elements",
  headers={"Authorization": f"Bearer {api_token}"}
)
assert r.ok
print(r.json())
```

{% endtab %}

{% tab title="felt-python" %}

```python
import os

from felt_python import list_elements

# Setting your API token as an env variable can save
# you from repeating it in every function call
os.environ["FELT_API_TOKEN"] = "<YOUR_API_TOKEN>"

map_id = "<YOUR_MAP_ID>"

list_elements(map_id)
```

{% endtab %}
{% endtabs %}

## Listing all annotation groups

Returns a list of GeoJSON Feature Collections, one for each annotation group.

{% tabs %}
{% tab title="curl" %}

```bash
curl \
  -H "Authorization: Bearer ${FELT_API_TOKEN}" \
  "https://felt.com/api/v2/maps/${MAP_ID}/element_groups"
```

{% endtab %}

{% tab title="Python" %}

```python
r = requests.get(
  f"https://felt.com/api/v2/maps/{map_id}/element_groups",
  headers={"Authorization": f"Bearer {api_token}"}
)
assert r.ok
print(r.json())
```

{% endtab %}

{% tab title="felt-python" %}

```python
from felt_python import list_element_groups

list_element_groups(map_id)
```

{% endtab %}
{% endtabs %}

## Create or update annotations

Each annotation is represented by a feature in the `POST`ed GeoJSON Feature Collection.

For each feature, including an existing annotation ID (`felt:id`) will result in the annotation being updated on the map. If the ID is omitted or does not match an existing annotation, a new annotation is created.

Styling is controlled with `felt:`-prefixed properties on each feature — for example `felt:color`, `felt:opacity`, `felt:strokeWidth`, `felt:strokeStyle`, `felt:size`, and `felt:text` for text annotations. Properties without the `felt:` prefix are stored as the annotation's data attributes. Request bodies are limited to 1 MB, and very complex geometries may be simplified on import.

{% tabs %}
{% tab title="curl" %}

```bash
curl \
  -X POST \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer ${FELT_API_TOKEN}" \
  "https://felt.com/api/v2/maps/${MAP_ID}/elements" \
  -d '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{},"geometry":{"coordinates":[[[15.478752514432728,15.576176978045694],[15.478752514432728,4.005934587045303],[29.892174099255755,4.005934587045303],[29.892174099255755,15.576176978045694],[15.478752514432728,15.576176978045694]]],"type":"Polygon"}}]}'
```

{% endtab %}

{% tab title="Python" %}

```python
new_elements = {
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      # Include "felt:id" in properties to update an existing annotation.
      # "felt:" properties control styling; anything else is stored as data.
      "properties": {"felt:color": "#2674BA"},
      "geometry": {
        "coordinates": [
          [
            [
              15.478752514432728,
              15.576176978045694
            ],
            [
              15.478752514432728,
              4.005934587045303
            ],
            [
              29.892174099255755,
              4.005934587045303
            ],
            [
              29.892174099255755,
              15.576176978045694
            ],
            [
              15.478752514432728,
              15.576176978045694
            ]
          ]
        ],
        "type": "Polygon"
      }
    }
  ]
}

r = requests.post(
  f"https://felt.com/api/v2/maps/{map_id}/elements",
  headers={"Authorization": f"Bearer {api_token}"},
  json=new_elements
)
assert r.ok
print(r.json())
```

{% endtab %}

{% tab title="felt-python" %}

```python
from felt_python import upsert_elements

new_elements = {
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "properties": {},
      "geometry": {
        "coordinates": [
          [
            [
              15.478752514432728,
              15.576176978045694
            ],
            [
              15.478752514432728,
              4.005934587045303
            ],
            [
              29.892174099255755,
              4.005934587045303
            ],
            [
              29.892174099255755,
              15.576176978045694
            ],
            [
              15.478752514432728,
              15.576176978045694
            ]
          ]
        ],
        "type": "Polygon"
      }
    }
  ]
}

upsert_elements(map_id, new_elements)
```

{% endtab %}
{% endtabs %}

## Delete an annotation

Delete an annotation by its ID. Annotation IDs are returned as the `felt:id` property when [listing annotations](#listing-all-annotations-on-a-map).

{% tabs %}
{% tab title="curl" %}

```bash
curl \
  -X DELETE \
  -H "Authorization: Bearer ${FELT_API_TOKEN}" \
  "https://felt.com/api/v2/maps/${MAP_ID}/elements/${ELEMENT_ID}"
```

{% endtab %}

{% tab title="Python" %}

```python
element_id = "<YOUR_ELEMENT_ID>"

r = requests.delete(
  f"https://felt.com/api/v2/maps/{map_id}/elements/{element_id}",
  headers={"Authorization": f"Bearer {api_token}"},
)
assert r.ok
```

{% endtab %}

{% tab title="felt-python" %}

```python
from felt_python import delete_element

element_id = "<YOUR_ELEMENT_ID>"

delete_element(map_id, element_id)
```

{% endtab %}
{% endtabs %}


---

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```
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