<div class="section-label"><span class="num">04</span> Payload Limits</div>
<div class="section-title">Keep POST bodies under <em>10 MB</em>.</div>
Every HTTP POST to the CSA Prediction Engine API must stay at or under **10 MB**. Larger bodies are rejected with **413 Payload Too Large**.
This limit applies to direct integrations (`curl`, `requests`, and similar). The [[API/Python API Client/Introduction|v2 Python client]] can upload large input objects through an alternate channel before it posts the prediction task.
> [!note]
> If you call the API yourself, you are responsible for payload size. The Python client’s large-object path is not available to raw HTTP clients.
## Keep payloads small
- Drop columns and rows you do not need for the task.
- Encode compact JSON (no indentation, tight separators).
- Prefer single-precision values — see [[API/Getting Started/Precision|Precision]].
```python
payload = json.dumps(variables, indent=None, separators=(',', ':'), cls=Float32Encoder)
```
## If you receive 413
Confirm the encoded size before retrying. Trim the body, then post again. Watch payload size as N and K grow; a wide <span class="mono">X</span> is usually the dominant cost.
## Related
- [[API/Introduction|API]]
- [[API/Getting Started/Precision|Precision]] · [[API/Getting Started/Throttle Limits|Throttle Limits]]
- [[API/Python API Client/Introduction|Python Client]]