---
name: cuOpt Server API Python
slug: cuopt-server-api-python
category: DevOps
description: cuOpt Server API Python provides REST server deployment and Python/curl client examples for NVIDIA cuOpt routing and LP/MILP problems. Use it when starting the server, understanding endpoints, or writing client code.
github: "https://github.com/NVIDIA/skills/tree/main/skills/cuopt-server-api-python"
language: Python
stars: 2973
forks: 345
install: "npx degit https://github.com/NVIDIA/skills/tree/main/skills/cuopt-server-api-python ~/.claude/skills/cuopt-server-api-python"
installs_to: ~/.claude/skills/cuopt-server-api-python
source_path: skills/cuopt-server-api-python/SKILL.md
collection_size: 25
category_size: 798
collection_url: "https://dirskills.com/collections/NVIDIA/skills"
added: 2026-08-17T07:09:35.406Z
last_synced: 2026-08-17T07:09:35.406Z
canonical_url: "https://dirskills.com/skills/cuopt-server-api-python"
---

# cuOpt Server API Python

cuOpt Server API Python provides REST server deployment and Python/curl client examples for NVIDIA cuOpt routing and LP/MILP problems. Use it when starting the server, understanding endpoints, or writing client code.

**Install:**

```bash
npx degit https://github.com/NVIDIA/skills/tree/main/skills/cuopt-server-api-python ~/.claude/skills/cuopt-server-api-python
```

## README

# cuOpt Server — Deploy and client (Python/curl)

This skill covers **starting the server** and **client examples** (curl, Python). Server has no separate C API (clients can be any language).

## Problem types supported

| Problem type | Supported |
|--------------|:---------:|
| Routing      | ✓         |
| LP           | ✓         |
| MILP         | ✓         |
| QP           | ✗         |

## Required questions

Ask these if not already clear:

1. **Problem type** — Routing or LP/MILP? (QP not available via REST.)
2. **Deployment** — Local, Docker, Kubernetes, or cloud?
3. **Client** — Which language or tool will call the API (e.g. Python, curl, another service)?

## Start server

```bash
# Development
python -m cuopt_server.cuopt_service --ip 0.0.0.0 --port 8000

# Docker
docker run --gpus all -d -p 8000:8000 -e CUOPT_SERVER_PORT=8000 \
  nvidia/cuopt:latest-cuda12.9-py3.13
```

## Verify

```bash
curl http://localhost:8000/cuopt/health
```

## Workflow

1. POST to `/cuopt/request` → get `reqId`
2. Poll `/cuopt/solution/{reqId}` until solution ready
3. Parse response

## Python client (routing)

```python
import requests, time
SERVER = "http://localhost:8000"
HEADERS = {"Content-Type": "application/json", "CLIENT-VERSION": "custom"}
payload = {
    "cost_matrix_data": {"data": {"0": [[0,10,15],[10,0,12],[15,12,0]]}},
    "travel_time_matrix_data": {"data": {"0": [[0,10,15],[10,0,12],[15,12,0]]}},
    "task_data": {"task_locations": [1, 2], "demand": [[10, 20]], "task_time_windows": [[0,100],[0,100]], "service_times": [5, 5]},
    "fleet_data": {"vehicle_locations": [[0, 0]], "capacities": [[50]], "vehicle_time_windows": [[0, 200]]},
    "solver_config": {"time_limit": 5}
}
r = requests.post(f"{SERVER}/cuopt/request", json=payload, headers=HEADERS)
req_id = r.json()["reqId"]
# Poll: GET /cuopt/solution/{req_id}
```

## Terminology: REST vs Python API

| Python API | REST |
|------------|------|
| order_locations | task_locations |
| set_order_time_windows() | task_time_windows |
| service_times | service_times |

Use `travel_time_matrix_data` (not transit_time_matrix_data). Capacities: `[[50, 50]]` not `[[50], [50]]`.

## Debugging (422 / payload)

**Validation errors:** Check field names against OpenAPI (`/cuopt.yaml`). Common mistakes: `transit_time_matrix_data` → `travel_time_matrix_data`; capacities per dimension `[[50, 50]]` not per vehicle `[[50], [50]]`. Capture `reqId` and response body for failed requests.

## Runnable assets

Run from each asset directory (server must be running; scripts exit 0 if server unreachable). All use Python `requests`:

- [assets/vrp_simple/](assets/vrp_simple/) — Basic VRP (no time windows)
- [assets/vrp_basic/](assets/vrp_basic/) — VRP with time windows
- [assets/pdp_basic/](assets/pdp_basic/) — Pickup and delivery
- [assets/lp_basic/](assets/lp_basic/) — LP via REST (CSR format)
- [assets/milp_basic/](assets/milp_basic/) — MILP via REST

See [assets/README.md](assets/README.md) for overview.

## Escalate

For contribution or build-from-source, see the developer skill.