FLUX.1 Kontext [dev]

Black-forest-labs

black-forest-labs/flux-1-kontext-devOpen Weights

Open-weight FLUX.1 Kontext model for instruction-based image editing

Benchmark Pricing$0.00 / 1M in$0.00 / 1M out

Context: 128,000 tokens•Max Output: 4,096 tokens•Released: 2025-05-29

TECHNICAL SPECIFICATIONS

Context Window128,000128K tokens

Max Output4,0964.1K tokens

LicenseFLUX.1 [dev] Non-Commercial LicenseSelf-hostable

Input Modalities

TextVision

Function / Tool CallingNot Supported

Structured OutputsPrompt Based

MODEL CONTEXT PROTOCOL (MCP) READINESS

⚠ FLUX.1 Kontext [dev] does not natively advertise tool-calling capabilities. When connecting to MCP servers, function calling must be handled via structured prompt injection.

MCP Context Window Recommendations

With a context capacity of 128,000 tokens, this model can handle moderately large MCP tool definitions and multi-turn conversation logs comfortably.

API CALL INVOCATION EXAMPLE

// Example: Calling FLUX.1 Kontext [dev] via OpenAI SDK
import OpenAI from "openai";

const client = new OpenAI({
  apiKey: process.env.BLACK-FOREST-LABS_API_KEY,
});

const response = await client.chat.completions.create({
  model: "black-forest-labs/flux-1-kontext-dev",
  messages: [{ role: "user", content: "Hello! Can you inspect MCP tools?" }],
});

console.log(response.choices[0].message.content);