Gemini generateContent

POST /v1beta/models/{model}:generateContent

Use the model name shown on the Pricing page.

Authentication

x-goog-api-key: OMROUTER_API_KEY
Content-Type: application/json

Path parameter

Parameter	Description
model	Model name, URL-encoded before it is placed in the path.

Request body

Field	Type	Required	Description
contents	array	Yes	Conversation content.
contents[].role	string	No	Common values are user and model.
contents[].parts	array	Yes	Text or supported multimodal parts.
generationConfig	object	No	Generation settings supported by the selected model.
systemInstruction	object	No	System instruction in Gemini format.
tools	array	No	Tool declarations where supported.

Example

curl --silent --show-error \
  "https://omrouter.com/v1beta/models/${OMROUTER_MODEL_ID}:generateContent" \
  --header "x-goog-api-key: $OMROUTER_API_KEY" \
  --header 'Content-Type: application/json' \
  --data '{
    "contents": [
      {
        "role": "user",
        "parts": [{"text": "Reply with one short sentence."}]
      }
    ]
  }'

Response

{
  "candidates": [
    {
      "content": {
        "role": "model",
        "parts": [{"text": "..."}]
      },
      "finishReason": "STOP"
    }
  ],
  "usageMetadata": {}
}

Some models return additional fields.

Streaming

Gemini streaming differs from OpenAI streaming. Use a client that supports Gemini streaming responses.

See the Gemini-compatible API guide for a complete direct HTTP example.