Sephir — Browser-native AI agent

A real AI agent in every browser tab. Reads, clicks, fills, compares — powered by your ChatGPT Plus or your own API keys.

Sephir is a real AI agent in every browser tab — reading pages, clicking buttons, filling forms, comparing tabs, and running multi-step work end to end. It runs on the AI accounts you already pay for. Sign in with your ChatGPT Plus subscription (OAuth via Codex), or bring your own API key for Claude, Gemini, OpenAI, Mistral, or OpenRouter. No extra subscription on top of what you already have. == What it does == • Runs background agents: up to three at once, each on its own job and its own model if you want. You keep talking while they work, can open any of them to watch, steer or stop it, and each answer comes back into the conversation. They ask the same permission prompts you would. • Reads the page you're on — from the selection toolbar or the side panel. • Compares two tabs side by side ("compare @tab[a] and @tab[b]"). • Extracts structured data into JSON using a schema you provide. • Answers questions about spreadsheets — attach a CSV or XLSX, or point it at a Google Sheet, and the sums and filters are computed rather than guessed. • Drives forms and pages — click, fill, type, navigate, wait for results — with a per-tool permission prompt the first time. • Uses a site's own tools when it publishes them, instead of clicking through the interface. • Summarizes YouTube videos with timestamps, transcript-aware. • Rewrites email in your tone using writing samples you pin. • Records a multi-step chat as a reusable workflow with {{variables}}, then replays it. • Installs agent skills from the skills.sh / GitHub registry. • Bookmarks any message and keeps it in one Saved list across conversations. • Exports any conversation to Markdown, JSON, or the clipboard. The audit timeline shows every tool call with its timestamp and arguments. == Privacy == Conversations, keys, and tokens stay in chrome.storage.local on your device. BYOK keys are encrypted at rest with a non-extractable key. BYOK requests go from your browser straight to the provider — we don't proxy them. No history sync by default. Usage telemetry is on by default and one switch in Settings turns it off. It counts events only, never prompts, page content, or the sites you visit. It is anonymous when you are signed out, and linked to your Sephir account when you are signed in. Full policy: https://sephir.app/privacy-policy == Pricing == The free tier with your own API key is unlimited. Pro starts with a 7-day trial and no card. Sephir Pro Lifetime is $39 one-time for the first 100 seats — no monthly subscription, ever, and a 30-day refund. == Feedback == Bugs and feature requests: hello@sephir.app, or sign in and use the feedback form at https://sephir.app/feedback