We now support VLMs in smolagents!
We just gave sight to smolagents
You hypocrite, first take the log out of your own eye, and then you will see clearly to take the speck out of your brother's eye. Matthew 7, 3-5
TL;DR
We have added vision support to smolagents, which unlocks the use of vision language models in agentic pipelines natively.
Table of Contents
Overview
In the agentic world, many capabilities are hidden behind a vision wall. A common example is web browsing: web pages feature rich visual content that you never fully recover by simply extracting their text, be it the relative position of objects, messages transmitted through color, specific icons… In this case, vision is a real superpower for agents. So we just added this capability to our smolagents!
Teaser of what this gives: an agentic browser that navigates the web in complete autonomy!
Here's an example of what it looks like:
How we gave sight to smolagents
🤔 How do we want to pass images to agents? Passing an image can be done in two ways:
You can have images directly available to the agent at start. This is often the case for Document AI.
Sometimes, images need to be added dynamically. A good example is when a web browser just performed an action, and needs to see the impact on its viewports.
1. Pass images once at agent start
For the case where we want to pass images at once, we added the possibility to pass a list of images to the agent in the run method: agent.run("Describe these images:", images=[image_1, image_2]) .
These image inputs are then stored in the task_images attribute of TaskStep along with the prompt of the task that you'd like to accomplish.
When running the agent, they will be passed to the model. This comes in handy with cases like taking actions based on long PDFs that include visual elements.
2. Pass images at each step ⇒ use a callback
How to dynamically add images into the agent’s memory?
To find out, we first need to understand how our agents work.
All agents in smolagents are based on the singular MultiStepAgent class, which is an abstraction of the ReAct framework. On a basic level, this class performs actions on a cycle of following steps, where existing variables and knowledge are incorporated into the agent logs as follows:
Initialization: the system prompt is stored in a
SystemPromptStep, and the user query is logged into aTaskStep.ReAct Loop (While):
Use
agent.write_inner_memory_from_logs()to write the agent logs into a list of LLM-readable chat messages.Send these messages to a
Modelobject to get its completion. Parse the completion to get the action (a JSON blob forToolCallingAgent, a code snippet forCodeAgent).Execute the action and logs result into memory (an
ActionStep).At the end of each step, run all callback functions defined in
agent.step_callbacks. ⇒ This is where we added support to images: make a callback that logs images into memory!
The figure below details this process:
As you can see, for use cases where images are dynamically retrieved (e.g. web browser agent), we support adding images to the model’s ActionStep, in attribute step_log.observation_images.
This can be done via a callback, which will be run at the end of each step.
Let's demonstrate how to make such a callback, and using it to build a web browser agent.👇👇
How to create a Web browsing agent with vision
We’re going to use helium. It provides browser automations based on selenium: this will be an easier way for our agent to manipulate webpages.
pip install "smolagents[all]" helium selenium python-dotenvThe agent itself can use helium directly, so no need for specific tools: it can directly use helium to perform actions, such as click("top 10") to click the button named "top 10" visible on the page. We still have to make some tools to help the agent navigate the web: a tool to go back to the previous page, and another tool to close pop-ups, because these are quite hard to grab for helium since they don’t have any text on their close buttons.
from io import BytesIO
from time import sleep
import helium
from dotenv import load_dotenv
from PIL import Image
from selenium import webdriver
from selenium.common.exceptions import ElementNotInteractableException, TimeoutException
from selenium.webdriver.common.by import By
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.support.ui import WebDriverWait
from smolagents import CodeAgent, LiteLLMModel, OpenAIServerModel, TransformersModel, tool
from smolagents.agents import ActionStep
load_dotenv()
import os
@tool
def search_item_ctrl_f(text: str, nth_result: int = 1) -> str:
"""
Searches for text on the current page via Ctrl + F and jumps to the nth occurrence.
Args:
text: The text to search for
nth_result: Which occurrence to jump to (default: 1)
"""
elements = driver.find_elements(By.XPATH, f"//*[contains(text(), '{text}')]")
if nth_result > len(elements):
raise Exception(f"Match n°{nth_result} not found (only {len(elements)} matches found)")
result = f"Found {len(elements)} matches for '{text}'."
elem = elements[nth_result - 1]
driver.execute_script("arguments[0].scrollIntoView(true);", elem)
result += f"Focused on element {nth_result} of {len(elements)}"
return result
@tool
def go_back() -> None:
"""Goes back to previous page."""
driver.back()
@tool
def close_popups() -> str:
"""
Closes any visible modal or pop-up on the page. Use this to dismiss pop-up windows! This does not work on cookie consent banners.
"""
# Common selectors for modal close buttons and overlay elements
modal_selectors = [
"button[class*='close']",
"[class*='modal']",
"[class*='modal'] button",
"[class*='CloseButton']",
"[aria-label*='close']",
".modal-close",
".close-modal",
".modal .close",
".modal-backdrop",
".modal-overlay",
"[class*='overlay']"
]
wait = WebDriverWait(driver, timeout=0.5)
for selector in modal_selectors:
try:
elements = wait.until(
EC.presence_of_all_elements_located((By.CSS_SELECTOR, selector))
)
for element in elements:
if element.is_displayed():
try:
# Try clicking with JavaScript as it's more reliable
driver.execute_script("arguments[0].click();", element)
except ElementNotInteractableException:
# If JavaScript click fails, try regular click
element.click()
except TimeoutException:
continue
except Exception as e:
print(f"Error handling selector {selector}: {str(e)}")
continue
return "Modals closed"For now, the agent has no visual input. So let us demonstrate how to dynamically feed it images in its step logs by using a callback. We make a callback save_screenshot that will be run at the end of each step.
def save_screenshot(step_log: ActionStep, agent: CodeAgent) -> None:
sleep(1.0) # Let JavaScript animations happen before taking the screenshot
driver = helium.get_driver()
current_step = step_log.step_number
if driver is not None:
for step_logs in agent.logs: # Remove previous screenshots from logs for lean processing
if isinstance(step_log, ActionStep) and step_log.step_number <= current_step - 2:
step_logs.observations_images = None
png_bytes = driver.get_screenshot_as_png()
image = Image.open(BytesIO(png_bytes))
print(f"Captured a browser screenshot: {image.size} pixels")
step_log.observations_images = [image.copy()] # Create a copy to ensure it persists, important!
# Update observations with current URL
url_info = f"Current url: {driver.current_url}"
step_log.observations = url_info if step_logs.observations is None else step_log.observations + "\n" + url_info
returnThe most important line here is when we add the image in our observations images: step_log.observations_images = [image.copy()].
This callback accepts both the step_log, and the agent itself as arguments. Having agent as an input allows to perform deeper operations than just modifying the last logs.
Let's make a model. We've added support for images in all models. Just one precision: when using TransformersModel with a VLM, for it to work properly you need to pass flatten_messages_as_text as False upon initialization, like:
model = TransformersModel(model_id="HuggingFaceTB/SmolVLM-Instruct", device_map="auto", flatten_messages_as_text=False)For this demo, let's use a bigger Qwen2VL via Fireworks API:
model = OpenAIServerModel(
api_key=os.getenv("FIREWORKS_API_KEY"),
api_base="https://api.fireworks.ai/inference/v1",
model_id="accounts/fireworks/models/qwen2-vl-72b-instruct",
)Now let’s move on to defining our agent. We set the highest verbosity_level to display the LLM’s full output messages to view its thoughts, and we increased max_steps to 20 to give the agent more steps to explore the web. We also provide it with our callback save_screenshot defined above.
agent = CodeAgent(
tools=[go_back, close_popups, search_item_ctrl_f],
model=model,
additional_authorized_imports=["helium"],
step_callbacks = [save_screenshot],
max_steps=20,
verbosity_level=2
)Finally, we provide our agent with some guidance about using helium.
helium_instructions = """
You can use helium to access websites. Don't bother about the helium driver, it's already managed.
First you need to import everything from helium, then you can do other actions!
Code:
```py
from helium import *
go_to('github.com/trending')
```<end_code>
You can directly click clickable elements by inputting the text that appears on them.
Code:
```py
click("Top products")
```<end_code>
If it's a link:
Code:
```py
click(Link("Top products"))
```<end_code>
If you try to interact with an element and it's not found, you'll get a LookupError.
In general stop your action after each button click to see what happens on your screenshot.
Never try to login in a page.
To scroll up or down, use scroll_down or scroll_up with as an argument the number of pixels to scroll from.
Code:
```py
scroll_down(num_pixels=1200) # This will scroll one viewport down
```<end_code>
When you have pop-ups with a cross icon to close, don't try to click the close icon by finding its element or targeting an 'X' element (this most often fails).
Just use your built-in tool `close_popups` to close them:
Code:
```py
close_popups()
```<end_code>
You can use .exists() to check for the existence of an element. For example:
Code:
```py
if Text('Accept cookies?').exists():
click('I accept')
```<end_code>
Proceed in several steps rather than trying to solve the task in one shot.
And at the end, only when you have your answer, return your final answer.
Code:
```py
final_answer("YOUR_ANSWER_HERE")
```<end_code>
If pages seem stuck on loading, you might have to wait, for instance `import time` and run `time.sleep(5.0)`. But don't overuse this!
To list elements on page, DO NOT try code-based element searches like 'contributors = find_all(S("ol > li"))': just look at the latest screenshot you have and read it visually, or use your tool search_item_ctrl_f.
Of course, you can act on buttons like a user would do when navigating.
After each code blob you write, you will be automatically provided with an updated screenshot of the browser and the current browser url.
But beware that the screenshot will only be taken at the end of the whole action, it won't see intermediate states.
Don't kill the browser.
"""Running the agent
Now everything's ready: Let’s run our agent!
github_request = """
I'm trying to find how hard I have to work to get a repo in github.com/trending.
Can you navigate to the profile for the top author of the top trending repo, and give me their total number of commits over the last year?
"""
agent.run(github_request + helium_instructions)Note, however, that this task is really hard: depending on the VLM that you use, this might not always work. Strong VLMs like Qwen2VL-72B or GPT-4o succeed more often.
Next Steps
This will give you a glimpse of the capabilities of a vision-enabled CodeAgent, but there’s much more to do!
You can get started with the agentic web browser here.
Read more about smolagents in our announcement blog post.
We are looking forward to seeing what you will build with vision language models and smolagents!
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