POST

chat

completions

Create a chat completion

curl --request POST \
  --url https://api.morphllm.com/v1/chat/completions \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data @- <<EOF
{
  "model": "morph-v3-fast",
  "messages": [
    {
      "role": "user",
      "content": "<instruction>I will add error handling</instruction>\n<code>function divide(a, b) {\n  return a / b;\n}</code>\n<update>function divide(a, b) {\n  if (b === 0) throw new Error('Division by zero');\n  return a / b;\n}</update>"
    }
  ],
  "stream": false,
  "max_tokens": 150,
  "temperature": 0
}
EOF

import requests

url = "https://api.morphllm.com/v1/chat/completions"

payload = {
    "model": "morph-v3-fast",
    "messages": [
        {
            "role": "user",
            "content": "<instruction>I will add error handling</instruction>
<code>function divide(a, b) {
  return a / b;
}</code>
<update>function divide(a, b) {
  if (b === 0) throw new Error('Division by zero');
  return a / b;
}</update>"
        }
    ],
    "stream": False,
    "max_tokens": 150,
    "temperature": 0
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    model: 'morph-v3-fast',
    messages: [
      {
        role: 'user',
        content: '<instruction>I will add error handling</instruction>\n<code>function divide(a, b) {\n  return a / b;\n}</code>\n<update>function divide(a, b) {\n  if (b === 0) throw new Error(\'Division by zero\');\n  return a / b;\n}</update>'
      }
    ],
    stream: false,
    max_tokens: 150,
    temperature: 0
  })
};

fetch('https://api.morphllm.com/v1/chat/completions', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.morphllm.com/v1/chat/completions",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'model' => 'morph-v3-fast',
    'messages' => [
        [
                'role' => 'user',
                'content' => '<instruction>I will add error handling</instruction>
<code>function divide(a, b) {
  return a / b;
}</code>
<update>function divide(a, b) {
  if (b === 0) throw new Error(\'Division by zero\');
  return a / b;
}</update>'
        ]
    ],
    'stream' => false,
    'max_tokens' => 150,
    'temperature' => 0
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.morphllm.com/v1/chat/completions"

	payload := strings.NewReader("{\n  \"model\": \"morph-v3-fast\",\n  \"messages\": [\n    {\n      \"role\": \"user\",\n      \"content\": \"<instruction>I will add error handling</instruction>\\n<code>function divide(a, b) {\\n  return a / b;\\n}</code>\\n<update>function divide(a, b) {\\n  if (b === 0) throw new Error('Division by zero');\\n  return a / b;\\n}</update>\"\n    }\n  ],\n  \"stream\": false,\n  \"max_tokens\": 150,\n  \"temperature\": 0\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.morphllm.com/v1/chat/completions")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"model\": \"morph-v3-fast\",\n  \"messages\": [\n    {\n      \"role\": \"user\",\n      \"content\": \"<instruction>I will add error handling</instruction>\\n<code>function divide(a, b) {\\n  return a / b;\\n}</code>\\n<update>function divide(a, b) {\\n  if (b === 0) throw new Error('Division by zero');\\n  return a / b;\\n}</update>\"\n    }\n  ],\n  \"stream\": false,\n  \"max_tokens\": 150,\n  \"temperature\": 0\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.morphllm.com/v1/chat/completions")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"model\": \"morph-v3-fast\",\n  \"messages\": [\n    {\n      \"role\": \"user\",\n      \"content\": \"<instruction>I will add error handling</instruction>\\n<code>function divide(a, b) {\\n  return a / b;\\n}</code>\\n<update>function divide(a, b) {\\n  if (b === 0) throw new Error('Division by zero');\\n  return a / b;\\n}</update>\"\n    }\n  ],\n  \"stream\": false,\n  \"max_tokens\": 150,\n  \"temperature\": 0\n}"

response = http.request(request)
puts response.read_body

{
  "id": "chatcmpl-123",
  "object": "chat.completion",
  "created": 1677652288,
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "\ndef calculate_total(items):\n    total = 0\n    for item in items:\n        total += item.price\n    return total * 1.1  # Add 10% tax\n"
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 25,
    "completion_tokens": 32,
    "total_tokens": 57
  }
}

{
  "error": {
    "code": "invalid_request_error",
    "message": "The request body is missing the `model` field."
  }
}

{
  "error": {
    "code": "unauthorized",
    "message": "Invalid API key provided."
  }
}

{
  "error": {
    "code": "rate_limited",
    "message": "Too many requests. Retry in 12 seconds."
  }
}

{
  "error": {
    "code": "internal_error",
    "message": "Something went wrong on our side."
  }
}

🔒 CONFIDENTIAL - INTERNAL USE ONLYThis page contains proprietary enterprise API documentation and is linked to your account. Do not share any information mentioned here with anyone external to your company. This documentation is for internal development and integration purposes only.

Quickstart

Switch to instruction-guided editing with 98% accuracy in 3 steps.

Prerequisites

Enterprise API key from your Morph account
Access to https://api.morphllm.com/v1/

Model	Speed	Accuracy	Input Limit	Output Limit
morph-v3-fast	10,500+ tok/sec	96%	16k tokens	16k tokens
morph-v3-large	5000+ tok/sec	98%	16k tokens	16k tokens
auto	5000-10,500tok/sec	98%	16k tokens	16k tokens

1. Configure Your Edit Tool

Set up your AI agent to generate the proper instructions guided format for the highest accuracy editing.

XML Tool
JSON Tool (Simple)

Edit File Tool Description:

Use this tool to make an edit to an existing file.

This will be read by a less intelligent model, which will quickly apply the edit. You should make it clear what the edit is, while also minimizing the unchanged code you write.
When writing the edit, you should specify each edit in sequence, with the special comment // ... existing code ... to represent unchanged code in between edited lines.

For example:

// ... existing code ...
FIRST_EDIT
// ... existing code ...
SECOND_EDIT
// ... existing code ...
THIRD_EDIT
// ... existing code ...

You should still bias towards repeating as few lines of the original file as possible to convey the change.
But, each edit should contain minimally sufficient context of unchanged lines around the code you're editing to resolve ambiguity.
DO NOT omit spans of pre-existing code (or comments) without using the // ... existing code ... comment to indicate its absence. If you omit the existing code comment, the model may inadvertently delete these lines.
If you plan on deleting a section, you must provide context before and after to delete it. If the initial code is ```code \n Block 1 \n Block 2 \n Block 3 \n code```, and you want to remove Block 2, you would output ```// ... existing code ... \n Block 1 \n  Block 3 \n // ... existing code ...```.
Make sure it is clear what the edit should be, and where it should be applied.
ALWAYS make all edits to a file in a single edit_file instead of multiple edit_file calls to the same file. The apply model can handle many distinct edits at once.

Parameters:

target_filepath (string, required): The path of the target file to modify
instructions (string, required): A single sentence written in the first person describing what you’re changing. Used to help disambiguate uncertainty in the edit.
code_edit (string, required): Specify ONLY the precise lines of code that you wish to edit. Use // ... existing code ... for unchanged sections.

Tool Definition:

{
  "name": "edit_file",
  "description": "Use this tool to make an edit to an existing file.\n\nThis will be read by a less intelligent model, which will quickly apply the edit. You should make it clear what the edit is, while also minimizing the unchanged code you write.\nWhen writing the edit, you should specify each edit in sequence, with the special comment // ... existing code ... to represent unchanged code in between edited lines.\n\nFor example:\n\n// ... existing code ...\nFIRST_EDIT\n// ... existing code ...\nSECOND_EDIT\n// ... existing code ...\nTHIRD_EDIT\n// ... existing code ...\n\nYou should still bias towards repeating as few lines of the original file as possible to convey the change.\nBut, each edit should contain minimally sufficient context of unchanged lines around the code you're editing to resolve ambiguity.\nDO NOT omit spans of pre-existing code (or comments) without using the // ... existing code ... comment to indicate its absence. If you omit the existing code comment, the model may inadvertently delete these lines.\nIf you plan on deleting a section, you must provide context before and after to delete it. If the initial code is ```code \\n Block 1 \\n Block 2 \\n Block 3 \\n code```, and you want to remove Block 2, you would output ```// ... existing code ... \\n Block 1 \\n  Block 3 \\n // ... existing code ...```.\nMake sure it is clear what the edit should be, and where it should be applied.\nALWAYS make all edits to a file in a single edit_file instead of multiple edit_file calls to the same file. The apply model can handle many distinct edits at once.",
  "parameters": {
    "properties": {
      "target_filepath": {
        "type": "string",
        "description": "Path of the target file to modify."
      },
      "instructions": {
        "type": "string",
        "description": "A single sentence instruction describing what you are going to do for the sketched edit. This is used to assist the less intelligent model in applying the edit. Use the first person to describe what you are going to do. Use it to disambiguate uncertainty in the edit."
      },
      "code_edit": {
        "type": "string",
        "description": "Specify ONLY the precise lines of code that you wish to edit. NEVER specify or write out unchanged code. Instead, represent all unchanged code using the comment of the language you're editing in - example: // ... existing code ..."
      }
    },
    "required": ["target_filepath", "instructions", "code_edit"]
  }
}

The instructions field should be generated by your AI model, not user input. Follow the tool description above nearly verbatim - terminology like “use it to disambiguate uncertainty in the edit” should be used. Example: “I am adding error handling to the user authentication function”

2. Send to Morph Enterprise API

import { OpenAI } from 'openai';

const client = new OpenAI({
  apiKey: 'your-enterprise-api-key',
  baseURL: 'https://api.morphllm.com/v1'
});

const testOriginalCode = `
const a = 1
const b = 2
function add(a, b) {
  return a + b
}

function subtract(a, b) {
  return a - b
}

const authenticateUser () => {
  return "Authenticated"
}
`;

// Test data - your agent should generate these
const testInstruction = "I will add the real user authentication function and remove the old authentication method";

const testUpdateSnippet = `
  // ... existing code ...
const authenticateUser = (email, password) => {
  const result = await verifyUser(email, password)
  if (result) {
    return "Authenticated"
  } else {
    return "Unauthenticated"
  }
}
`;

async function applyEnterpriseEdit(
  instruction: string, 
  originalCode: string, 
  updateSnippet: string
): Promise<string> {
  const response = await client.chat.completions.create({
    model: "morph-v3-fast",
    messages: [
      {
        role: "user",
        content: `<instruction>${instruction}</instruction>\n<code>${originalCode}</code>\n<update>${updateSnippet}</update>`
      }
    ]
  });
  
  return response.choices[0].message.content || '';
}

// Example usage
async function main() {
  try {
    const finalCode = await applyEnterpriseEdit(
      testInstruction, 
      testOriginalCode, 
      testUpdateSnippet
    );
    console.log("Final merged code:");
    console.log(finalCode);
  } catch (error) {
    console.error("Error applying edit:", error);
  }
}

// Run the example
main();

import openai
import asyncio

client = openai.OpenAI(
    api_key="your-enterprise-api-key",
    base_url="https://api.morphllm.com/v1"
)

test_original_code = """
const a = 1
const b = 2
def add(a, b):
  return a + b
}

def subtract(a, b):
  return a - b
}

def authenticateUser ():
  return "Authenticated"
}
"""

# Test data - your agent should generate these
test_instruction = "I will add the real user authentication function and remove the old authentication method" # This is the instruction that your agent should generate

test_update_snippet = """
def authenticateUser (email, password) => {
  # ... existing code ...
  result = await verifyUser(email, password)
  if (result) {
    return "Authenticated"
  } else {
    return "Unauthenticated"
  }
}
"""

def apply_enterprise_edit(instruction: str, original_code: str, update_snippet: str):
    """Apply an enterprise edit using Morph's instruction-guided editing."""
    response = client.chat.completions.create(
        model="morph-v3-fast",
        messages=[
            {
                "role": "user",
                "content": f"<instruction>{instruction}</instruction>\n<code>{original_code}</code>\n<update>{update_snippet}</update>"
            }
        ]
    )
    
    return response.choices[0].message.content

# Example usage
if __name__ == "__main__":
    final_code = apply_enterprise_edit(
        test_instruction, 
        test_original_code, 
        test_update_snippet
    )
    print("Final merged code:")
    print(final_code)

3. Handle the Response

Extract the merged code from the enterprise API response. Response Format:

final_code = response.choices[0].message.content

Extract the Final Code:

const finalCode = response.choices[0].message.content;
// Write to file or return to your application
await fs.writeFile(targetFile, finalCode);

final_code = response.choices[0].message.content
# Write to file or return to your application  
with open(target_file, 'w') as f:
    f.write(final_code)

Enterprise Features

Perfect Accuracy

Instruction-guided editing achieves 98% accuracy on complex code changes

44k Input Tokens

Handle entire large files, complete modules, and complex codebases

36k Output Tokens

Generate complete implementations, full refactors, and comprehensive updates

Migration from Standard API:

Enterprise API requires an <instruction> field but maintains backward compatibility with existing <update> patterns.

Authorizations

Authorization

string

header

required

Morph API key, passed as Authorization: Bearer sk-.... Create keys at https://www.morphllm.com/dashboard/api-keys.

Body

application/json

Chat completion request for Apply or Warp Grep (OpenAI-compatible)

Morph Apply
Warp Grep

Either a Morph Apply request or a Warp Grep request, discriminated by model.

model

enum<string>

default:morph-v3-fast

required

ID of the Apply model to use, or auto to let the router choose

Available options:

morph-v3-fast,

morph-v3-large,

auto

Example:

"morph-v3-fast"

messages

object[]

required

Array containing a single user message with structured content using instruction-guided format

Show child attributes

Example:

[
  {
    "role": "user",
    "content": "<instruction>I will add error handling</instruction>\n<code>function divide(a, b) {\n  return a / b;\n}</code>\n<update>function divide(a, b) {\n  if (b === 0) throw new Error('Division by zero');\n  return a / b;\n}</update>"
  }
]

stream

boolean

default:false

Enable streaming response. When true the response is a text/event-stream of OpenAI-style chat.completion.chunk deltas terminated by data: [DONE].

Example:

false

max_tokens

integer

Maximum number of tokens the Apply model may generate

Example:

150

temperature

number

default:0

Sampling temperature for the Apply request (0.0 for deterministic output)

Example:

0

Response

Chat completion response

Completion returned by a Morph chat model.

string

required

Unique identifier for the completion

Example:

"chatcmpl-123"

object

string

required

Always chat.completion

Example:

"chat.completion"

created

integer

required

Unix timestamp of when the completion was created

Example:

1677652288

choices

object[]

required

List of completion choices

Show child attributes

Example:

[
  {
    "index": 0,
    "message": {
      "role": "assistant",
      "content": "\ndef calculate_total(items):\n    total = 0\n    for item in items:\n        total += item.price\n    return total * 1.1  # Add 10% tax\n"
    },
    "finish_reason": "stop"
  }
]

usage

object

required

Usage statistics for the completion request

Show child attributes

Example:

{
  "prompt_tokens": 25,
  "completion_tokens": 32,
  "total_tokens": 57
}

Create a chat completion

curl --request POST \
  --url https://api.morphllm.com/v1/chat/completions \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data @- <<EOF
{
  "model": "morph-v3-fast",
  "messages": [
    {
      "role": "user",
      "content": "<instruction>I will add error handling</instruction>\n<code>function divide(a, b) {\n  return a / b;\n}</code>\n<update>function divide(a, b) {\n  if (b === 0) throw new Error('Division by zero');\n  return a / b;\n}</update>"
    }
  ],
  "stream": false,
  "max_tokens": 150,
  "temperature": 0
}
EOF

import requests

url = "https://api.morphllm.com/v1/chat/completions"

payload = {
    "model": "morph-v3-fast",
    "messages": [
        {
            "role": "user",
            "content": "<instruction>I will add error handling</instruction>
<code>function divide(a, b) {
  return a / b;
}</code>
<update>function divide(a, b) {
  if (b === 0) throw new Error('Division by zero');
  return a / b;
}</update>"
        }
    ],
    "stream": False,
    "max_tokens": 150,
    "temperature": 0
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    model: 'morph-v3-fast',
    messages: [
      {
        role: 'user',
        content: '<instruction>I will add error handling</instruction>\n<code>function divide(a, b) {\n  return a / b;\n}</code>\n<update>function divide(a, b) {\n  if (b === 0) throw new Error(\'Division by zero\');\n  return a / b;\n}</update>'
      }
    ],
    stream: false,
    max_tokens: 150,
    temperature: 0
  })
};

fetch('https://api.morphllm.com/v1/chat/completions', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.morphllm.com/v1/chat/completions",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'model' => 'morph-v3-fast',
    'messages' => [
        [
                'role' => 'user',
                'content' => '<instruction>I will add error handling</instruction>
<code>function divide(a, b) {
  return a / b;
}</code>
<update>function divide(a, b) {
  if (b === 0) throw new Error(\'Division by zero\');
  return a / b;
}</update>'
        ]
    ],
    'stream' => false,
    'max_tokens' => 150,
    'temperature' => 0
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.morphllm.com/v1/chat/completions"

	payload := strings.NewReader("{\n  \"model\": \"morph-v3-fast\",\n  \"messages\": [\n    {\n      \"role\": \"user\",\n      \"content\": \"<instruction>I will add error handling</instruction>\\n<code>function divide(a, b) {\\n  return a / b;\\n}</code>\\n<update>function divide(a, b) {\\n  if (b === 0) throw new Error('Division by zero');\\n  return a / b;\\n}</update>\"\n    }\n  ],\n  \"stream\": false,\n  \"max_tokens\": 150,\n  \"temperature\": 0\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.morphllm.com/v1/chat/completions")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"model\": \"morph-v3-fast\",\n  \"messages\": [\n    {\n      \"role\": \"user\",\n      \"content\": \"<instruction>I will add error handling</instruction>\\n<code>function divide(a, b) {\\n  return a / b;\\n}</code>\\n<update>function divide(a, b) {\\n  if (b === 0) throw new Error('Division by zero');\\n  return a / b;\\n}</update>\"\n    }\n  ],\n  \"stream\": false,\n  \"max_tokens\": 150,\n  \"temperature\": 0\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.morphllm.com/v1/chat/completions")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"model\": \"morph-v3-fast\",\n  \"messages\": [\n    {\n      \"role\": \"user\",\n      \"content\": \"<instruction>I will add error handling</instruction>\\n<code>function divide(a, b) {\\n  return a / b;\\n}</code>\\n<update>function divide(a, b) {\\n  if (b === 0) throw new Error('Division by zero');\\n  return a / b;\\n}</update>\"\n    }\n  ],\n  \"stream\": false,\n  \"max_tokens\": 150,\n  \"temperature\": 0\n}"

response = http.request(request)
puts response.read_body

{
  "id": "chatcmpl-123",
  "object": "chat.completion",
  "created": 1677652288,
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "\ndef calculate_total(items):\n    total = 0\n    for item in items:\n        total += item.price\n    return total * 1.1  # Add 10% tax\n"
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 25,
    "completion_tokens": 32,
    "total_tokens": 57
  }
}

{
  "error": {
    "code": "invalid_request_error",
    "message": "The request body is missing the `model` field."
  }
}

{
  "error": {
    "code": "unauthorized",
    "message": "Invalid API key provided."
  }
}

{
  "error": {
    "code": "rate_limited",
    "message": "Too many requests. Retry in 12 seconds."
  }
}

{
  "error": {
    "code": "internal_error",
    "message": "Something went wrong on our side."
  }
}

Get Started

Models

API Reference

Integrations

Enterprise Apply

Quickstart

Prerequisites

1. Configure Your Edit Tool

2. Send to Morph Enterprise API

3. Handle the Response

Enterprise Features

Perfect Accuracy

44k Input Tokens

36k Output Tokens

Authorizations

Body

Response

​Quickstart

​Prerequisites

​1. Configure Your Edit Tool

​2. Send to Morph Enterprise API

​3. Handle the Response

​Enterprise Features

Perfect Accuracy

44k Input Tokens

36k Output Tokens

Authorizations

Body

Response

Quickstart

Prerequisites

1. Configure Your Edit Tool

2. Send to Morph Enterprise API

3. Handle the Response

Enterprise Features