Gemini 3 Flash

Text Generation • Google

google/gemini-3-flash

• Third-party
• Zero data retention

Gemini 3 Flash is Google's fast multimodal model with frontier intelligence, superior search, and grounding capabilities.

Usage

const response = await env.AI.run(
  'google/gemini-3-flash',
  { contents: [{ parts: [{ text: 'What are the three laws of thermodynamics?' }], role: 'user' }] },
)
console.log(response)

curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run \
  --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "model": "google/gemini-3-flash",
  "input": {
    "contents": [
      {
        "parts": [
          {
            "text": "What are the three laws of thermodynamics?"
          }
        ],
        "role": "user"
      }
    ]
  }
}'

While there are technically four laws (starting with the "Zeroth Law"), the **Three Laws of Thermodynamics** are the fundamental principles that describe how energy, heat, and matter behave.

Here is a breakdown of the three laws:

---

### 1. The First Law: Conservation of Energy
**Definition:** Energy cannot be created or destroyed, only transformed from one form to another. The total energy of an isolated system remains constant.

*   **In simple terms:** You can't get something for nothing.
*   **The Equation:** $\Delta U = Q - W$
    *   ($\Delta U$ is the change in internal energy, $Q$ is heat added, and $W$ is work done by the system).
*   **Example:** In a car engine, the chemical energy of the gasoline is converted into heat and then into mechanical work to move the car.

### 2. The Second Law: Entropy
**Definition:** The total entropy (disorder) of an isolated system can never decrease over time; it can only remain constant or increase. This law dictates the "arrow of time."

*   **In simple terms:** Things tend to get messy and disorganized over time. Heat always flows spontaneously from a hotter object to a colder object, never the other way around without adding work.
*   **Key Concept:** This law explains why 100% efficiency is impossible—some energy is always "lost" as waste heat.
*   **Example:** If you place a hot cup of coffee in a cold room, the coffee cools down as heat spreads into the room. The heat will never spontaneously jump back from the room into the coffee to make it boil again.

### 3. The Third Law: Absolute Zero
**Definition:** As the temperature of a system approaches absolute zero ($0$ Kelvin or $-273.15^\circ$ Celsius), the entropy of a perfect crystal approaches a constant minimum (usually zero).

*   **In simple terms:** You can’t reach absolute zero.
*   **Key Concept:** As atoms get colder, they slow down. At absolute zero, all molecular motion would essentially stop. However, because moving heat requires a temperature difference, it is physically impossible to reach a temperature of exactly zero Kelvin in a finite number of steps.
*   **Example:** Scientists use advanced lasers and magnets to get atoms within billionths of a degree of absolute zero, but they can never quite hit the "stop" button entirely.

---

### Summary Mnemonic
There is a famous (and slightly cynical) way to remember these laws, often called **"Ginsberg’s Theorem"**:

1.  **First Law:** You can't win. (You can't get more energy out than you put in).
2.  **Second Law:** You can't break even. (You always lose some energy to entropy).
3.  **Third Law:** You can't get out of the game. (You can't reach absolute zero to stop the process).

***

**Note on the Zeroth Law:** If you ever hear about a "Zeroth Law," it simply states that if two systems are each in thermal equilibrium with a third system, they are in thermal equilibrium with each other. This is the law that allows us to use thermometers.

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            "text": "While there are technically four laws (starting with the \"Zeroth Law\"), the **Three Laws of Thermodynamics** are the fundamental principles that describe how energy, heat, and matter behave.\n\nHere is a breakdown of the three laws:\n\n---\n\n### 1. The First Law: Conservation of Energy\n**Definition:** Energy cannot be created or destroyed, only transformed from one form to another. The total energy of an isolated system remains constant.\n\n*   **In simple terms:** You can't get something for nothing.\n*   **The Equation:** $\\Delta U = Q - W$\n    *   ($\\Delta U$ is the change in internal energy, $Q$ is heat added, and $W$ is work done by the system).\n*   **Example:** In a car engine, the chemical energy of the gasoline is converted into heat and then into mechanical work to move the car.\n\n### 2. The Second Law: Entropy\n**Definition:** The total entropy (disorder) of an isolated system can never decrease over time; it can only remain constant or increase. This law dictates the \"arrow of time.\"\n\n*   **In simple terms:** Things tend to get messy and disorganized over time. Heat always flows spontaneously from a hotter object to a colder object, never the other way around without adding work.\n*   **Key Concept:** This law explains why 100% efficiency is impossible—some energy is always \"lost\" as waste heat.\n*   **Example:** If you place a hot cup of coffee in a cold room, the coffee cools down as heat spreads into the room. The heat will never spontaneously jump back from the room into the coffee to make it boil again.\n\n### 3. The Third Law: Absolute Zero\n**Definition:** As the temperature of a system approaches absolute zero ($0$ Kelvin or $-273.15^\\circ$ Celsius), the entropy of a perfect crystal approaches a constant minimum (usually zero).\n\n*   **In simple terms:** You can’t reach absolute zero.\n*   **Key Concept:** As atoms get colder, they slow down. At absolute zero, all molecular motion would essentially stop. However, because moving heat requires a temperature difference, it is physically impossible to reach a temperature of exactly zero Kelvin in a finite number of steps.\n*   **Example:** Scientists use advanced lasers and magnets to get atoms within billionths of a degree of absolute zero, but they can never quite hit the \"stop\" button entirely.\n\n---\n\n### Summary Mnemonic\nThere is a famous (and slightly cynical) way to remember these laws, often called **\"Ginsberg’s Theorem\"**:\n\n1.  **First Law:** You can't win. (You can't get more energy out than you put in).\n2.  **Second Law:** You can't break even. (You always lose some energy to entropy).\n3.  **Third Law:** You can't get out of the game. (You can't reach absolute zero to stop the process).\n\n***\n\n**Note on the Zeroth Law:** If you ever hear about a \"Zeroth Law,\" it simply states that if two systems are each in thermal equilibrium with a third system, they are in thermal equilibrium with each other. This is the law that allows us to use thermometers.",
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          }
        ]
      },
      "finishReason": "STOP"
    }
  ],
  "usageMetadata": {
    "promptTokenCount": 8,
    "candidatesTokenCount": 697,
    "totalTokenCount": 1107,
    "trafficType": "ON_DEMAND",
    "promptTokensDetails": [
      {
        "modality": "TEXT",
        "tokenCount": 8
      }
    ],
    "candidatesTokensDetails": [
      {
        "modality": "TEXT",
        "tokenCount": 697
      }
    ],
    "thoughtsTokenCount": 402
  },
  "modelVersion": "gemini-3-flash-preview",
  "createTime": "2026-07-24T21:49:35.132185Z",
  "responseId": "791jatmICOSg3dAPo6eioAg",
  "gatewayMetadata": {
    "keySource": "Unified"
  }
}

Examples

<details>

<summary>With System Instruction — Using a system instruction to set context</summary>

const response = await env.AI.run(
  'google/gemini-3-flash',
  {
    contents: [{ parts: [{ text: 'How do I read a JSON file in Python?' }], role: 'user' }],
    generationConfig: { temperature: 0.3 },
    systemInstruction: {
      parts: [{ text: 'You are a helpful coding assistant specializing in Python.' }],
    },
  },
)
console.log(response)

curl https://api.cloudflare.com/client/v4/accounts/$CLOUDFLARE_ACCOUNT_ID/ai/run \
  --header "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
  --header "Content-Type: application/json" \
  --data '{
  "model": "google/gemini-3-flash",
  "input": {
    "contents": [
      {
        "parts": [
          {
            "text": "How do I read a JSON file in Python?"
          }
        ],
        "role": "user"
      }
    ],
    "generationConfig": {
      "temperature": 0.3
    },
    "systemInstruction": {
      "parts": [
        {
          "text": "You are a helpful coding assistant specializing in Python."
        }
      ]
    }
  }
}'

``` To read a JSON file in Python, you use the built-injson` module.

Here is the most common and recommended way to do it:

The Standard Method

```python import json