ProphetBest AI Sidebar Extensions for Chrome in 2026
Last updated: March 2026
The Chrome side panel has become the preferred home for AI assistants. Instead of interrupting your workflow with popups or requiring you to switch tabs, sidebar extensions sit alongside the page you are working on. This side-by-side approach is particularly powerful for tasks like summarizing articles while reading them, writing emails with AI suggestions visible next to the compose window, or automating form filling on the active page.
We tested the top AI sidebar extensions to compare their capabilities, usability, and value. The biggest differentiator we found is whether the sidebar can only read web pages or actually interact with them. Extensions that offer browser automation from the sidebar enable a fundamentally different class of workflows compared to chat-only tools.
Prophet
Claude AI side panel with browser automation
Pricing: Free tier, Pro $9.99/mo, Premium $29.99/mo, Ultra $59.99/mo
Prophet is purpose-built for the Chrome side panel. It opens alongside any web page and provides Claude AI chat with full browser automation capabilities. The key differentiator is that Prophet does not just read pages; it can interact with them. Using 18 built-in browser tools powered by the accessibility tree and Chrome DevTools Protocol, Prophet can click buttons, fill forms, navigate between pages, extract structured data, and manage tabs. This makes it the only sidebar extension that functions as a true AI agent capable of completing multi-step web tasks on your behalf. The pay-per-use credit system charges only for actual API usage, and the open-source codebase provides full transparency into how your data is handled. Prophet supports Claude Haiku 4.5 for fast simple tasks, Sonnet 4.6 for balanced workloads, and Opus 4.6 for complex reasoning.
Pros
- +True browser automation from the sidebar (click, fill, navigate, extract)
- +Accessibility tree approach is faster and more reliable than screenshot-based methods
- +Pay-per-use credits rather than wasted flat subscriptions
- +Open source on GitHub for full code transparency
- +Persistent chat history with conversation management
Cons
- -Claude-only; no option to switch to GPT or Gemini models
- -Newer extension compared to established competitors
- -Automation requires granting DevTools debugging permissions
Monica
Multi-model AI sidebar with broad feature set
Pricing: Free tier, Pro $9.90/mo, Unlimited $19.90/mo
Monica provides a well-designed sidebar interface with access to GPT-4o, Claude 3.5 Sonnet, and Gemini models. The sidebar offers quick-access tools for summarizing the current page, translating selected text, rewriting content, and having open-ended conversations. Monica also includes image generation and an AI-powered search feature. The multi-model flexibility is its strongest point: you can switch between GPT, Claude, and Gemini depending on the task without leaving the sidebar. For users who want a general-purpose AI assistant without browser automation, Monica is the most polished option. The free tier is usable but limited in daily queries, and the Unlimited plan still caps usage of the most expensive models.
Pros
- +Multi-model support with easy switching between GPT-4o, Claude, and Gemini
- +Polished and intuitive sidebar design
- +Built-in image generation and AI search
- +Strong translation and rewriting tools
Cons
- -No browser automation capabilities
- -Unlimited plan still has daily caps on premium models
- -Sidebar can feel cluttered with too many features
Sider
Reading and writing companion in the sidebar
Pricing: Free tier, Basic $8.99/mo, Pro $12.99/mo, Unlimited $24.99/mo
Sider focuses on being a reading and writing companion that lives in your Chrome sidebar. It provides contextual tools that adapt based on what you are doing: reading an article triggers summary and explanation tools, composing an email triggers writing assistance, viewing code triggers explanation features. The unique group chat feature lets you send the same prompt to multiple AI models simultaneously and compare their responses side by side. This is genuinely useful for tasks where model quality varies. Sider supports ChatGPT, Claude, and Gemini. The sidebar layout is clean and organized into tabs for chat, tools, and history. For users focused on content consumption and creation, Sider is a strong choice, though it lacks the automation features that power users may need.
Pros
- +Context-aware tools that adapt to the current page
- +Group chat compares answers from multiple models simultaneously
- +Clean sidebar with organized tabs for chat, tools, and history
- +Competitive entry-level pricing at $8.99/mo
Cons
- -No browser automation or page interaction
- -Unlimited plan is expensive at $24.99/mo
- -Group chat can be slow when querying multiple models
MaxAI
Quick-action AI sidebar for selected text
Pricing: Free tier, Pro $9.99/mo, Elite $19.99/mo
MaxAI takes a different approach to the sidebar by emphasizing quick actions over extended conversations. Select text on any page and the sidebar instantly offers options like summarize, explain, translate, rewrite, and reply. This makes MaxAI extremely fast for short tasks. It also enhances Google search results by adding AI summaries directly in the search page sidebar. MaxAI supports GPT-4o, Claude, Gemini, and Llama models. The sidebar is minimal by design, which is both a strength (fast, uncluttered) and a limitation (less suitable for long conversations or complex multi-turn tasks). For users who primarily need quick AI actions on selected text rather than extended dialogue, MaxAI is efficient and well-designed.
Pros
- +Fastest workflow for quick AI actions on selected text
- +AI summaries integrated into Google search results
- +Minimal, uncluttered sidebar design
- +Broad model support including Llama for open-source enthusiasts
Cons
- -Less suited for extended conversations or complex tasks
- -No browser automation capabilities
- -Free tier heavily restricted in daily usage
Merlin
AI sidebar with web search integration
Pricing: Free tier, Pro $14.25/mo, Team $12/mo per user
Merlin offers a sidebar that combines AI chat with real-time web search. When you ask a question, Merlin can search the internet for current information before generating a response, making it particularly useful for research tasks that require up-to-date data. The sidebar includes tools for summarizing the current page, analyzing uploaded documents, and generating content. Merlin also offers team plans with shared usage, which is uncommon among sidebar extensions. The web search integration is the standout feature that justifies the higher price point. However, the sidebar interface is less polished than Monica or Sider, and the free tier is quite limited.
Pros
- +Real-time web search for up-to-date information
- +Document upload and analysis from the sidebar
- +Team plans with shared usage quotas
- +Good for research tasks requiring current data
Cons
- -Higher starting price than most competitors
- -Sidebar interface less polished than Monica or Sider
- -Free tier limited to roughly 50 queries per day
Harpa AI
AI sidebar with web monitoring and custom commands
Pricing: Free (BYOK), Pro $15/mo, Business custom
Harpa AI operates in the sidebar with a focus on web monitoring and custom automation commands. You can set up alerts to track price changes on e-commerce sites, monitor web pages for content updates, and create custom command sequences for repetitive tasks. The bring-your-own-API-key model means you can use the sidebar for free with your own GPT-4 or Claude API keys. Harpa supports local AI models as well, which appeals to privacy-conscious users. The sidebar interface is functional but complex, with a steeper learning curve than other options. For power users who want monitoring and custom commands alongside AI chat, Harpa is the most capable option in that specific niche.
Pros
- +Web monitoring and price alerts from the sidebar
- +Custom command sequences for automation
- +Free usage with your own API keys
- +Local AI model support for privacy
Cons
- -Steep learning curve for custom commands
- -Sidebar interface is functional but not intuitive
- -Monitoring automation is not interactive (cannot fill forms or click)
Sidebar Extensions at a Glance
| Extension | Browser Automation | Multi-Model | Web Search | Starting Price |
|---|---|---|---|---|
| Prophet | Yes (18 tools) | Claude only | No | $9.99/mo |
| Monica | No | Yes | Yes | $9.90/mo |
| Sider | No | Yes | No | $8.99/mo |
| MaxAI | No | Yes | Yes | $9.99/mo |
| Merlin | No | Yes | Yes | $14.25/mo |
| Harpa AI | Monitoring only | Yes | No | $15/mo |
Frequently Asked Questions
What is an AI sidebar extension?
An AI sidebar extension opens a panel on the side of your Chrome browser, alongside the web page you are viewing. Unlike popup extensions that block the page, sidebar extensions let you interact with AI while keeping the full webpage visible. This side-by-side layout is ideal for tasks like summarizing articles, writing emails, or getting AI assistance while filling out forms.
What is the difference between a sidebar extension and a popup extension?
A sidebar extension uses Chrome's built-in side panel API to open a persistent panel next to your web page. It stays open as you navigate between pages and does not block any content. A popup extension opens a small window when you click its icon, which closes when you click elsewhere. Sidebar extensions are better for tasks that require ongoing interaction, while popups are suited for quick one-off actions.
Can AI sidebar extensions interact with web pages?
Most AI sidebar extensions can read the content of the current web page, but only a few can interact with it. Prophet is unique in offering full browser automation from the sidebar: it can click buttons, fill forms, navigate pages, and extract data. Other extensions like Monica and Sider can read page content for summarization but cannot take actions on the page.
Do sidebar extensions slow down my browser?
Quality sidebar extensions have minimal performance impact when not actively processing. They load in a separate browser context and do not inject heavy scripts into every page. You may notice brief increases in memory usage when the sidebar is open and processing AI responses. Extensions that inject content scripts into every page (some popup-based tools) tend to have more impact than pure sidebar extensions.