Messages

File Analysis

Image and document analysis using the Claude Messages API.

The Messages API supports multimodal input via content blocks in the content array. Use image blocks for images and document blocks for PDFs and other files.

Endpoint and authentication are the same as Create a Message.

Confirm that the selected model supports the media type. A file_id must come from an upload accessible to the same service and account; this page does not define an upload endpoint, and another provider’s file ID is not interchangeable. URLs must be reachable by the server; local paths are not remote file URLs.

The current local gateway does not implement /v1/files uploads. Start with this page's URL or Base64 input examples. Use file_id examples only when your deployment provides uploads and you already have an ID accessible to the same account.

Content Block Types

Type	Description
`text`	Text prompt accompanying the media input
`image`	Image input via URL, base64, or file ID
`document`	Document input (PDF, plain text, etc.) via URL, base64, or file ID

Image Analysis

Image from URL

json

{
  "model": "claude-sonnet-4-6",
  "max_tokens": 1024,
  "messages": [
    {
      "role": "user",
      "content": [
        {
          "type": "image",
          "source": {
            "type": "url",
            "url": "https://example.com/image.jpg"
          }
        },
        {
          "type": "text",
          "text": "Describe this image"
        }
      ]
    }
  ]
}

Image from base64

json

{
  "model": "claude-sonnet-4-6",
  "max_tokens": 1024,
  "messages": [
    {
      "role": "user",
      "content": [
        {
          "type": "image",
          "source": {
            "type": "base64",
            "media_type": "image/jpeg",
            "data": "/9j/4AAQSkZJRg..."
          }
        },
        {
          "type": "text",
          "text": "What objects are visible in this image?"
        }
      ]
    }
  ]
}

Document Analysis

Analyze a PDF document:

json

{
  "model": "claude-sonnet-4-6",
  "max_tokens": 1024,
  "messages": [
    {
      "role": "user",
      "content": [
        {
          "type": "document",
          "source": {
            "type": "url",
            "url": "https://example.com/report.pdf"
          }
        },
        {
          "type": "text",
          "text": "Summarize the key findings in this document."
        }
      ]
    }
  ]
}

Request Example

See language setup. Set API_KEY and replace model, file URL, and ID placeholders first. Each version displays the raw response to the same request.

cURLPythonJavaScriptJava

bash

curl --fail-with-body --silent --show-error --max-time 180 \
  --request POST \
  --url "https://api.tokatlas.ai/v1/messages" \
  --header "x-api-key: $API_KEY" \
  --header "anthropic-version: 2023-06-01" \
  --header "Content-Type: application/json" \
  --data '{
  "model": "claude-sonnet-4-6",
  "max_tokens": 1024,
  "messages": [
    {
      "role": "user",
      "content": [
        {
          "type": "image",
          "source": {
            "type": "url",
            "url": "https://example.com/image.jpg"
          }
        },
        {
          "type": "text",
          "text": "Describe this image"
        }
      ]
    }
  ]
}'

python

import os
import requests

headers = {
    'x-api-key': os.environ["API_KEY"],
    'anthropic-version': '2023-06-01',
    'Content-Type': 'application/json',
}
payload = {'model': 'claude-sonnet-4-6',
 'max_tokens': 1024,
 'messages': [{'role': 'user',
               'content': [{'type': 'image',
                            'source': {'type': 'url',
                                       'url': 'https://example.com/image.jpg'}},
                           {'type': 'text', 'text': 'Describe this image'}]}]}
response = requests.request(
    'POST', 'https://api.tokatlas.ai/v1/messages', headers=headers,
    json=payload,
    timeout=180,
)
response.raise_for_status()
print(response.text)

if (!process.env.API_KEY) throw new Error("Set API_KEY first.");
const response = await fetch("https://api.tokatlas.ai/v1/messages", {
  method: "POST",
  headers: {
    "x-api-key": process.env.API_KEY,
    "anthropic-version": "2023-06-01",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
  "model": "claude-sonnet-4-6",
  "max_tokens": 1024,
  "messages": [
    {
      "role": "user",
      "content": [
        {
          "type": "image",
          "source": {
            "type": "url",
            "url": "https://example.com/image.jpg"
          }
        },
        {
          "type": "text",
          "text": "Describe this image"
        }
      ]
    }
  ]
}),
  signal: AbortSignal.timeout(180_000),
});
if (!response.ok) {
  throw new Error(`HTTP ${response.status}: ${await response.text()}`);
}
console.log(await response.text());

java

import java.net.URI;
import java.net.http.*;
import java.time.Duration;

public class Example {
    public static void main(String[] args) throws Exception {
        String apiKey = System.getenv("API_KEY");
        if (apiKey == null || apiKey.isBlank()) {
            throw new IllegalArgumentException("Set API_KEY first.");
        }
        String payload = String.join("\n",
            "{",
            "  \"model\": \"claude-sonnet-4-6\",",
            "  \"max_tokens\": 1024,",
            "  \"messages\": [",
            "    {",
            "      \"role\": \"user\",",
            "      \"content\": [",
            "        {",
            "          \"type\": \"image\",",
            "          \"source\": {",
            "            \"type\": \"url\",",
            "            \"url\": \"https://example.com/image.jpg\"",
            "          }",
            "        },",
            "        {",
            "          \"type\": \"text\",",
            "          \"text\": \"Describe this image\"",
            "        }",
            "      ]",
            "    }",
            "  ]",
            "}"
        );
        HttpClient client = HttpClient.newBuilder()
            .connectTimeout(Duration.ofSeconds(30)).build();
        HttpRequest request = HttpRequest.newBuilder()
            .uri(URI.create("https://api.tokatlas.ai/v1/messages"))
            .timeout(Duration.ofSeconds(180))
            .header("x-api-key", apiKey)
            .header("anthropic-version", "2023-06-01")
            .header("Content-Type", "application/json")
            .method("POST", HttpRequest.BodyPublishers.ofString(payload))
            .build();
        HttpResponse<String> response = client.send(
            request, HttpResponse.BodyHandlers.ofString());
        if (response.statusCode() < 200 || response.statusCode() >= 300) {
            throw new IllegalStateException("HTTP " + response.statusCode() + ": "
                + response.body());
        }
        System.out.println(response.body());
    }
}

Response Example

json

{
  "code": 200,
  "data": {
    "id": "msg_013Zva2CMHLNnXjNJJKqJ2EF",
    "type": "message",
    "role": "assistant",
    "content": [
      {
        "type": "text",
        "text": "This image shows a scenic landscape with a boardwalk path through a green meadow under a blue sky with scattered clouds."
      }
    ],
    "model": "claude-sonnet-4-6",
    "stop_reason": "end_turn",
    "usage": {
      "input_tokens": 1520,
      "output_tokens": 42
    }
  }
}

Create a Message — Text conversation and streaming
Tool Calling — Function calling and tool use

File Analysis ​

Content Block Types ​

Image Analysis ​

Image from URL ​

Image from base64 ​

Document Analysis ​

Request Example ​

Response Example ​

Related Topics ​

File Analysis

Content Block Types

Image Analysis

Image from URL

Image from base64

Document Analysis

Request Example

Response Example

Related Topics