Hermes Browser Extension

Browser-native side panel for Hermes Agent — connect active web context through a local gateway, Hermes Cloud, or a self-hosted remote gateway.

Created by Jon Komet (@abundantbeing). Community extension for Hermes Agent by Nous Research. MIT licensed.

What it is

Hermes Browser Extension is not a browser chatbot. It is a Chromium side panel or Firefox sidebar for the real Hermes Agent runtime. Hermes Control is complete on Chromium and restricted on Firefox, where it can read pages, open addresses and manage tabs but cannot click or type (what works on Firefox). Choose a local gateway, attach to a signed-in Hermes Cloud agent tab, or connect to a self-hosted remote API/dashboard. Local and remote API connections can use the models, tools, skills, sessions, memory, and MCP servers already configured in Hermes; Cloud and dashboard-ticket connections are intentionally Chat-only.

• Bot Mode brings your Hermes agent roster into the panel: switch agents, edit profiles, and run group chats where several agents reply in one room. Current group-chat limitation: page-context delivery is not yet reliable; do not assume group bots can see the active page. Hermes Control is not shown in group chats. Individual bot chats retain their existing page-context and control behavior. Chat-only and remote group turns do not capture page context.
• File attachments show one card per file per message. Open previews the file, Open on computer reveals the original file's containing folder through local Hermes, and Save downloads a copy.
• Tab screenshot stages the visible, approved page as an image attachment when you choose it from the attachment menu. Screenshots are never captured automatically.
• Hermes Control sets which tabs Hermes may operate: This tab, Selected tabs, or a Task set of tabs you pick explicitly.
• Live sessions: running chats are highlighted in Sessions. On gateways that expose live sessions, reopen a working chat to follow its reply and tool activity. Supported live sessions offer Steer, Queue, and Stop instead of idle send controls, and steers sent from another client appear in the followed transcript. On gateways with session authority, chats running in the CLI, Desktop or another window are listed too, and Stop is aimed at the run it was started for.
• Projects: on a dashboard connection to a gateway with session authority, the sessions drawer has a Recents | Projects strip. List projects, open one, start a session in its folder, create a project from a folder path on the machine running Hermes, or move a session to another project or folder. Where the gateway cannot do this, the tab says why and Recents keeps working.
• Response style and chat layout: Vivid UI (cards, tables and charts when they help), Rich text or Plain text, with bubbles on both sides or for your messages only. First-time setup walks through theme, font, style and layout, and ends with Connect to Hermes. Settings > Appearance & Themes can run it again. See guides/haui-v1.md.
• Context: each session's own context window, read from the gateway, with a ring in the composer. On gateways with session authority, Compact context replaces older messages with a summary and reads the session back before it says it worked.
• Capability states: Settings > About & Diagnostics shows what this connection can do (available, cached, unsupported and so on), with the reason, source and age, and the support report prints the same rows.
• Tool activity: a compact expandable list keeps calls out of the reply. Inspect individual calls, close the list without hiding thinking, and keep your place while activity updates.
• Message tools: Copy, Edit, and Restore checkpoint on supported turns, with day dividers, message times, and theme-aware bubbles. History refreshes keep the current question in place when Hermes merges older and newer turns, without hiding genuine repeated messages.
• Reasoning effort: a slider with tick marks, or buttons if you prefer. The choice is remembered. In a group chat each bot keeps its own effort.
• Hermes Assist drafts beside supported text composers and never sends, posts, or submits for you.
• Page comments: pick an element, write a note, and queue pins beside Ask Hermes.
• Settings: a category home opens one section at a time, with Back navigation, edited-category markers, and direct links from related controls.
• Appearance: Light, Dark, or System mode, twelve themes, text zoom, and a font list. Everforest has forest greens and warm parchment; Classic Hermes has amber gold and navy; Anti-Nous has crimson, navy reading panels, and fine gold trim. Nous Light keeps its white shell and Nous Blue accents. Centered background artwork changes when you open the panel and scales with its width; sidecar illustrations rotate independently.

The full list of changes per version lives in the changelog and the releases.

Visual tour

Screenshots use the Mono theme in Dark mode.

Requirements

• Hermes Agent installed and working.
• For Local or Remote API mode: Hermes Gateway/API server enabled locally or on a reachable remote machine. Hermes Cloud instead requires a signed-in HTTPS agent tab.
• Node.js 20+.
• Chrome, Edge, Brave, Comet, or another Chromium browser with Side Panel API support (Chrome 116+ baseline). Firefox 142+ is supported via AMO, the Mozilla Add-ons listing. npm run build:firefox is for local/dev Firefox builds only.

Firefox scope

Hermes Browser Extension on Firefox is a chat-and-context client with a restricted Hermes Control: pairing, the sidebar (declared with sidebar_action, not the Chromium side panel), streaming replies, attachments, and page-context capture all work, and Hermes Control can read the page, open addresses, scroll, take a screenshot you allow, and list, open, switch and close tabs. Firefox has no equivalent to Chromium's debugger API, so the Firefox package omits that permission, and