Use Gemini 3.1 Flash Lite with Comfy Router

API Reference for vertexai/gemini-3.1-flash-lite, served by Comfy Router from Google.

Quick start

Create a key at platform.comfy.org/profile/api-keys and export it as COMFY_API_KEY. The Python and TypeScript snippets use the Comfy SDKs (pip install comfy-sdk, npm install @comfyorg/sdk); the cURL snippet is the same call over raw HTTP. Model ID: vertexai/gemini-3.1-flash-lite Endpoint: POST https://api.comfy.org/v2/models/vertexai/gemini-3.1-flash-lite

from comfy_sdk import Comfy

# Reads COMFY_API_KEY from the environment. Each call sends a fresh
# Idempotency-Key and waits up to 10 minutes for the finished result.
with Comfy() as client:
    result = client.models.run(
        "vertexai/gemini-3.1-flash-lite",
        {
            # Request fields are the provider's own — see Input below.
        },
    )

print(result)

import { comfy } from "@comfyorg/sdk";

// Reads COMFY_API_KEY from the environment. Each call sends a fresh
// Idempotency-Key and waits up to 10 minutes for the finished result.
const { data } = await comfy.models.run("vertexai/gemini-3.1-flash-lite", {
  // Request fields are the provider's own — see Input below.
});

console.log(data);

# Request fields are the provider's own — see Input below.
curl https://api.comfy.org/v2/models/vertexai/gemini-3.1-flash-lite \
  -H "X-API-Key: $COMFY_API_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{}'

Schema

Input

Router has not published an authored input schema for this model yet: GET /v2/models/vertexai/gemini-3.1-flash-lite/openapi.json returns an open object with x-comfy-input-schema-authored: false. Router forwards the body to Google unchanged, so Google’s own API reference is authoritative for the request fields, and nothing is validated server side.

Output

object[]

object

object[]

string[]

integer

string

string (date)

Format: date

integer

string

object

The content of the current conversation with the model. For single-turn queries, this is a single instance. For multi-turn queries, this is a repeated field that contains conversation history and the latest request.

object[]

required

object

URI based data.

string

URI

string

The media type of the file specified in the data or fileUri fields. Acceptable values include the following. For gemini-2.0-flash-lite and gemini-2.0-flash, the maximum length of an audio file is 8.4 hours and the maximum length of a video file (without audio) is one hour. For more information, see Gemini audio and video requirements. Text files must be UTF-8 encoded. The contents of the text file count toward the token limit. There is no limit on image resolution.Possible values: application/pdf, audio/mpeg, audio/mp3, audio/wav, image/png, image/jpeg, image/webp, text/plain, video/mov, video/mpeg, video/mp4, video/mpg, video/avi, video/wmv, video/mpegps, video/flv

object

Inline data in raw bytes. For gemini-2.0-flash-lite and gemini-2.0-flash, you can specify up to 3000 images by using inlineData.

string (byte)

The base64 encoding of the image, PDF, or video to include inline in the prompt. When including media inline, you must also specify the media type (mimeType) of the data. Size limit: 20MBFormat: byte

string

A text prompt or code snippet.

boolean

Indicates this part is a thinking/reasoning step from the model.

string

required

Possible values: user, model

string

object[]

string

Possible values: HARM_CATEGORY_SEXUALLY_EXPLICIT, HARM_CATEGORY_HATE_SPEECH, HARM_CATEGORY_HARASSMENT, HARM_CATEGORY_DANGEROUS_CONTENT

string

The probability that the content violates the specified safety categoryPossible values: NEGLIGIBLE, LOW, MEDIUM, HIGH, UNKNOWN

string

Timestamp when the response was created.

string

The model version used to generate the response.

object

string

object[]

string

Possible values: HARM_CATEGORY_SEXUALLY_EXPLICIT, HARM_CATEGORY_HATE_SPEECH, HARM_CATEGORY_HARASSMENT, HARM_CATEGORY_DANGEROUS_CONTENT

string

The probability that the content violates the specified safety categoryPossible values: NEGLIGIBLE, LOW, MEDIUM, HIGH, UNKNOWN

string

Unique identifier for the response.

object

integer

Output only. Number of tokens in the cached part in the input (the cached content).

integer

Number of tokens in the response(s).

object[]

Breakdown of candidate tokens by modality.

string

Type of input or output content modality.Possible values: MODALITY_UNSPECIFIED, TEXT, IMAGE, VIDEO, AUDIO, DOCUMENT

integer

Number of tokens for the given modality.

integer

Number of tokens in the request. When cachedContent is set, this is still the total effective prompt size meaning this includes the number of tokens in the cached content.

object[]

Breakdown of prompt tokens by modality.

string

Type of input or output content modality.Possible values: MODALITY_UNSPECIFIED, TEXT, IMAGE, VIDEO, AUDIO, DOCUMENT

integer

Number of tokens for the given modality.

integer

Number of tokens present in thoughts output.

integer

Number of tokens present in tool-use prompt(s).

integer

Total number of tokens (prompt + candidates).

string

Traffic type used for the request (e.g., PROVISIONED_THROUGHPUT).

Examples

Output

{
  "candidates": [
    {
      "content": {
        "parts": [
          {
            "text": "A lighthouse stands at the edge of the harbour, its lamp still turning as the sun comes up."
          }
        ],
        "role": "model"
      },
      "finishReason": "STOP"
    }
  ],
  "modelVersion": "gemini-2.5-flash",
  "responseId": "0d1f2a3b-4c5d-6e7f-8a9b-0c1d2e3f4a5b",
  "usageMetadata": {
    "candidatesTokenCount": 21,
    "promptTokenCount": 12,
    "totalTokenCount": 33
  }
}

Before you ship

The snippets above are the shortest working call. Three things are the same for every model and are documented once on the Comfy Router headers page: send an Idempotency-Key on every paid call and reuse it when you retry, expect the connection to be held up to Router’s 10 minute deadline, and keep X-Comfy-Request-Id from every response. The SDKs do all three for you; the cURL tab does none of them. On failure, X-Comfy-Error-Type names the bucket, and a 422 means the body failed the model’s schema and was never billed.

Headers

Authentication, idempotency, request IDs, error buckets, retry pacing, spend limits.

Quick Start

Typed error handling in Python and TypeScript, reading the 422, walking the catalog.

Limitations

What Router does not do today, and what to use instead.

Develop with Comfy

Deploy ComfyUI

Run Workflows

Comfy Router

Comfy CLI

Specifications

Use Gemini 3.1 Flash Lite with Comfy Router

Quick start

Schema

Input

Output

Examples

Output

Before you ship

Headers

Quick Start

Limitations

​Quick start

​Schema

​Input

​Output

​Examples

​Output

​Before you ship

Headers

Quick Start

Limitations

Quick start

Schema

Input

Output

Examples

Output

Before you ship