> ## Documentation Index
> Fetch the complete documentation index at: https://astral-6ef288be-claude-ascii-globe-mouse-interaction-bupya.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# POST /contains

> Check if a geometry is inside another geometry

<Warning>
  **Research Preview** — This API is under development.
</Warning>

# Contains

Check if a geometry is inside a container geometry.

```
POST /compute/v0/contains
```

## Request Body

<ParamField body="chainId" type="number" required>
  Target chain ID (e.g., 84532 for Base Sepolia, 8453 for Base).
</ParamField>

<ParamField body="container" type="Input" required>
  The containing geometry (typically a polygon). Can be a UID, GeoJSON, or offchain attestation reference.
</ParamField>

<ParamField body="geometry" type="Input" required>
  The geometry to check. Can be a UID, GeoJSON, or offchain attestation reference.
</ParamField>

<ParamField body="schema" type="string" required>
  EAS schema UID to issue the attestation against.
</ParamField>

<ParamField body="recipient" type="string">
  Ethereum address to receive the attestation. Defaults to zero address if not provided.
</ParamField>

## Example Request

<CodeGroup>
  ```bash cURL theme={null}
  curl -X POST https://api.astral.global/compute/v0/contains \
    -H "Content-Type: application/json" \
    -d '{
      "chainId": 84532,
      "container": "0xpolygon...",
      "geometry": "0xpoint...",
      "schema": "0xschema...",
      "recipient": "0xdef456..."
    }'
  ```

  ```typescript TypeScript theme={null}
  const response = await fetch('https://api.astral.global/compute/v0/contains', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      chainId: 84532,
      container: '0xpolygon...',
      geometry: '0xpoint...',
      schema: '0xschema...',
      recipient: '0xdef456...'
    })
  });
  ```
</CodeGroup>

## Response

<ResponseField name="result" type="boolean" required>
  `true` if the geometry is inside the container, `false` otherwise
</ResponseField>

<ResponseField name="operation" type="string" required>
  Always "contains"
</ResponseField>

<ResponseField name="timestamp" type="number" required>
  Unix timestamp of computation
</ResponseField>

<ResponseField name="inputRefs" type="string[]" required>
  Array containing \[containerRef, geometryRef]
</ResponseField>

## Example Response

```json theme={null}
{
  "result": true,
  "operation": "contains",
  "timestamp": 1706400000,
  "inputRefs": [
    "0xpolygon...",
    "0xpoint..."
  ],
  "attestation": {
    "schema": "0x...",
    "attester": "0x...",
    "recipient": "0xdef456...",
    "data": "0x...",
    "signature": "0x..."
  },
  "delegatedAttestation": {
    "signature": "0x...",
    "attester": "0x...",
    "deadline": 1706403600
  }
}
```

## Notes

* Uses PostGIS `ST_Contains` function
* The container must completely contain the geometry for `true`
* Points on the boundary may return `false` (use `intersects` for boundary cases)

<Card title="SDK Method" icon="code" href="/sdk/compute#contains">
  See `astral.compute.contains()`
</Card>