API reference
Legacy text completions
Endpoints, request fields and response schemas for calling NeonAPI.
POST /v1/completions
Authentication
Use your NeonAPI API key in Authorization: Bearer YOUR_API_KEY. Keep the key in a trusted application environment.
Availability and compatibility
Check the selected model’s protocol, permissions, price and supported parameters before calling. Unsupported parameters may be rejected. Request examples use placeholders.
Request fields
application/json
| Field | Type | Required | Constraints | Meaning |
|---|---|---|---|---|
model | string | Yes | — | Exact published model ID. |
prompt | string / string[] | Yes | — | Instruction or generation prompt. |
max_tokens | integer | No | — | Output token limit; model-dependent. |
temperature | number | No | — | Sampling temperature where supported. |
top_p | number | No | — | Nucleus sampling probability. |
n | integer | No | — | Number of generated results; model limits apply. |
stream | boolean | No | — | Request incremental streaming events. |
stop | string / string[] | No | — | — |
suffix | string | No | — | — |
echo | boolean | No | — | — |
Full field definitions, nested objects and referenced schemas are available in the downloadable specification.
Request example
export NEON_API_KEY="YOUR_API_KEY"
curl https://neon-api.com/v1/completions \
-H "Authorization: Bearer $NEON_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "YOUR_MODEL_ID",
"prompt": "A quiet constellation above a midnight observatory"
}'Responses
Fields vary by model and protocol. The schema below describes the documented successful response; streams use protocol-specific events.
| Status | Meaning |
|---|---|
| 200 | Successful response |
Response schema
| Field | Type | Required | Constraints | Meaning |
|---|---|---|---|---|
id | string | No | — | Identifier returned for this result or task. |
object | string | No | — | — |
created | integer | No | — | — |
model | string | No | — | Exact published model ID. |
choices | object[] | No | — | Generated completion candidates. |
usage | Usage | No | — | Usage reported by the selected protocol. |
Download the user API OpenAPI specification
See errors and streaming & tasks.