Clef

cloudflare/clefOpen Weights

Cloudflare's open-weight decision model that returns probabilities for typed choice, score and yes/no questions about text or images

Benchmark Pricing$0.09 / 1M in$0.00 / 1M out

Context: 65,536 tokens•Max Output: 4,096 tokens•Released: 2026-10-01

TECHNICAL SPECIFICATIONS

Context Window65,53665.5K tokens

Max Output4,0964.1K tokens

LicenseApache-2.0Self-hostable

Input Modalities

TextVision

Function / Tool CallingNot Supported

Structured OutputsPrompt Based

MODEL CONTEXT PROTOCOL (MCP) READINESS

⚠ Clef 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 65,536 tokens, this model can handle compact tool sets. Consider keeping MCP server tool manifests minimal to preserve headroom.

API CALL INVOCATION EXAMPLE

// Example: Calling Clef via OpenAI SDK
import OpenAI from "openai";

const client = new OpenAI({
  apiKey: process.env.CLOUDFLARE_API_KEY,
});

const response = await client.chat.completions.create({
  model: "cloudflare/clef",
  messages: [{ role: "user", content: "Hello! Can you inspect MCP tools?" }],
});

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