The AI Second Brain · for links

Your AI second brain
for every link you save.

Capture from anywhere on the web. Cryptie auto-tags from the page context and the vocabulary you already use—so a library of thousands stays organized without filing.

Then plug it into the rest of your stack. Claude, ChatGPT, Obsidian, MCP, n8n, and any HTTP client share the same library through one REST API and Bearer token. Search it with tag: and domain: in the app, or let your agent ask for it directly.

AI auto-tagging • REST API + MCP • Claude / ChatGPT / Obsidian ready • Chrome extension • Built for huge libraries

Build Your Second Brain See AI Integrations Import Your Bookmarks →
Cryptie says
Capture · Auto-tag · Retrieve · Feed your AI. Your links, your second brain.
Link Crypt interface showing saved links with tags, search functionality, and clean dark UI

Clean interface with powerful search, tags, and link previews

The four jobs of an AI second brain

Tiago Forte's second brain runs on four steps: capture, organize, retrieve, and express. Link Crypt does all four for the URLs you collect — and now your AI assistants share the same library.

1 · Capture

Save from anywhere

Chrome extension, iOS share sheet, web app, or POST /links from an agent — one click puts a URL into the same crypt.

2 · Organize

Cryptie auto-tags

Built-in AI reads page context and proposes tags from your existing vocabulary, so new saves slot into your system instead of piling up untagged.

3 · Retrieve

Search that scales

Combine tag:ai, domain:github.com, and title: filters. Built for libraries in the hundreds or thousands.

4 · Express

Feed your AI

REST API + MCP server give Claude, ChatGPT, Obsidian, n8n, and anything HTTP read/write access — one Bearer token, same library.

Browser extension
Chrome / Edge / Brave

Save links instantly from any page

One-click saving from any webpage. Add tags, notes, and organize as you browse—works seamlessly across all your devices.

Add to Chrome — It's Free
Link Crypt Chrome Extension showing the save popup with URL, tags input, and save button
Who builds a second brain here

People who collect lots of links and want them back on demand — surfaced by their AI when it matters, not buried in folders.

Journalists & writers

Source lists, interview refs, background reading — tag by beat or story, then run domain: or tag: when you're on deadline.

Product & UX

Competitors, specs, user research — keep everything labeled and pull tag:competitor or domain: in one search.

Analysts & researchers

Datasets, papers, dashboards — large libraries stay usable when filters combine (e.g. tag:ai domain:arxiv.org).

PKM + AI second-brain stacks

Obsidian for notes, Claude / ChatGPT for reasoning, Link Crypt for URLs — wire the API and your agents save, search, and tag links without copy-paste.

From bookmarks to second brain in three steps
1
Capture & import

Sign up with email or magic link, install the Chrome extension, and pull in your old bookmarks from Chrome, Safari, Firefox, Edge, Pocket, Instapaper, or 10+ other services.

2
Let Cryptie organize

AI auto-tagging reuses your existing tag vocabulary on every new save. Browse and refine with tag: and domain: filters as the library grows.

3
Plug into your AI

Mint a Bearer token, then connect Claude, ChatGPT, Obsidian, MCP, or any HTTP client. Same library — no copy-paste.

Your second brain's nervous system

One Bearer token wires your library into every tool you already think with.

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See all integrations · REST API docs →

Questions
What is an “AI second brain” and how is Link Crypt one? +

The second brain idea (Tiago Forte) is an organized, searchable store of everything you capture from the web. In the AI era, that store is also the context your agents read. Link Crypt is the URL layer of a modern second brain: capture from the Chrome extension or any HTTP client, organize with Cryptie's auto-tagging, retrieve with tag: / domain: search, and express by giving Claude, ChatGPT, Obsidian, and any agent live read/write access to the same library.

What makes Link Crypt different from other bookmark managers? +

Link Crypt is an AI-organized link library built for retrieval at scale: Cryptie auto-tags every save from your existing vocabulary, you query with tag:ai domain:github.com, and a full REST API + MCP server lets Claude, ChatGPT, Obsidian, and your agents read and write the same library. Classic read-later apps optimize for in-app reading; we optimize for finding and feeding your AI.

Why not just use browser bookmarks? +

Built-in bookmarks break down when you have hundreds or thousands of URLs: shallow search, awkward folders, no portable query syntax, and no API for agents or automation. Link Crypt gives you structured tags, tag:/domain: search, cross-device sync, and programmatic access — so large libraries stay usable.

Who is Link Crypt for? +

Anyone who saves a lot of links and needs them back fast — journalists and writers, product and UX folks, analysts and researchers, and people wiring links into Obsidian, agents, or a second brain. If "where did I save that?" is a recurring question, Link Crypt is built for you.

Can I import my existing bookmarks? +

Yes! Link Crypt supports imports from Pocket, Instapaper, Raindrop.io, Pinboard, GoodLinks, Readwise, browser bookmarks, and 10+ other services. All tags and metadata are preserved during import. Exporting from your browser? Follow the HTML bookmark export guide.

How does Link Crypt's advanced search work? +

Use precise filters like tag:javascript, domain:github.com, title:tutorial, or description:api. Combine filters for surgical precision: tag:ai domain:arxiv.org finds all AI research papers instantly.

Is my data private and exportable? +

Absolutely. No social features, no ads, no data mining. Your links stay completely private. Export to CSV or JSON anytime—we'll never hold your data hostage.

Does Link Crypt work with Claude, ChatGPT, Obsidian, and other AI tools? +

Yes — the full REST API is on every plan, plus an MCP server (beta) for AI clients. Step-by-step setup guides: Claude & Claude Code, ChatGPT & Custom GPT, Obsidian + AI, plus the full integrations directory (n8n, Zapier, Make, Raycast, Notion, Readwise). One Bearer token from Preferences, one library, everything stays in sync.

Frequently Asked Questions

What is an AI second brain, and how is Link Crypt one?
The "second brain" idea (popularized by Tiago Forte) is an organized, searchable store of everything you capture from the web. In the AI era, that store is also the context your AI assistants read. Link Crypt is the URL layer of a modern AI second brain. It runs all four jobs end-to-end: capture from the Chrome extension or any HTTP client, organize with Cryptie's auto-tagging from your existing tag vocabulary, retrieve with tag: and domain: filters that scale to thousands of links, and express by giving Claude, ChatGPT, Obsidian, MCP clients, and any agent live read/write access through the REST API.
Which alternatives offer robust tagging and search for link management?
Link Crypt stands out for robust tagging and search at scale, plus Cryptie AI auto-tagging when you save or re-tag links. It is a link library built for retrieval and AI workflows, not a read-later reading app. You get unlimited tags and advanced syntax: tag:keyword (e.g. tag:ai), domain:website (e.g. domain:github.com), title:text, description:text, and combined queries like tag:ai domain:github.com. Imports from Pocket, Instapaper, and other services preserve tags. A full REST API and MCP server fit second-brain stacks (Obsidian) and AI agent workflows (Claude, Claude Code, ChatGPT, Custom GPT, n8n, Zapier, Manus, and more).
Who is Link Crypt for?
People building an AI second brain who save hundreds or thousands of links — journalists, writers, product managers, UX researchers, analysts, developers using Claude Code and Cursor, and anyone wiring Obsidian or AI agents into a PKM stack. If browser bookmarks or generic search stop working as your library grows, Link Crypt is built for that job.
Why use Link Crypt instead of browser bookmarks alone?
Browser bookmarks are fine for a small set of favorites. They strain when the count gets large: limited search, folder sprawl, no tag:/domain: query syntax, and no API for assistants or automation. Link Crypt adds structured tags, fast filtered search, sync across devices, export, and programmatic access — so big libraries stay manageable.
How do I import my existing bookmarks to Link Crypt?
Link Crypt supports imports from Pocket, Instapaper, Raindrop.io, Pinboard, GoodLinks, Readwise, browser bookmarks (Chrome, Safari, Firefox, Edge), and 10+ other services. Visit getlinkcrypt.com, create an account, click Import, select your service format, and upload your export file. Link Crypt preserves all URLs, titles, tags, descriptions, timestamps, and favorite status. For HTML exports from Chrome, Safari, Firefox, or Edge, use the dedicated browser bookmark import guide.
How do I export bookmarks from Chrome, Safari, Firefox, or Edge for Link Crypt?
Each browser can save an HTML bookmark file. Chrome: Bookmarks and lists → Bookmark Manager → menu → Export bookmarks. Safari (Mac): File → Export → Bookmarks. Firefox: Manage bookmarks (Ctrl+Shift+O or ⌘⇧O) → Import and Backup → Export Bookmarks to HTML. Edge: Settings and more → Favorites → More options → Export favorites. In Link Crypt, open Import Links and choose Browser Bookmarks (Chrome/Safari/Firefox/Edge). Full walkthrough: getlinkcrypt.com/browser-bookmarks-import.
How does Link Crypt compare to read-later apps for privacy?
Link Crypt is a private link library (optimized for saving and finding URLs). Read-later apps often emphasize in-app reading experience; we emphasize retrieval, export, and API access. Privacy highlights: Data ownership — full-library export in CSV and JSON anytime. No social features — your library is yours only. Auth — email/password or magic link, no Apple or Google required. Database security — Row-Level Security in PostgreSQL. No ads or data mining.
Which cross-platform tools sync links without requiring Apple ID?
Link Crypt is fully cross-platform and works on Windows, Mac, Linux, Android, iOS, and ChromeOS without requiring an Apple ID, iCloud account, or any vendor-specific ecosystem. The web app works in any browser, a Chrome extension is available for Chromium browsers, and an iOS native app provides a Share Extension. Authentication uses email/password or magic link. Links sync in real-time across all devices.
How much does Link Crypt cost compared to Instapaper and other bookmark managers?
Link Crypt costs $3.99 per month or $19.99 per year, making it significantly more affordable than competing services. Compared to Instapaper Premium which costs $5.99/month or $59.99/year, Link Crypt saves you 33% on monthly plans and 67% on annual plans. You get unlimited link storage, advanced tagging, powerful search syntax, full data export, and cross-platform sync. Free trial available with no credit card required.
What is the most affordable bookmark manager with advanced search?
Link Crypt is one of the most affordable bookmark managers with professional features at $3.99/month or $19.99/year. Link Crypt offers unlimited link storage, advanced tagging with search syntax, powerful filters, and full data export at a price much lower than alternatives like Instapaper Premium ($59.99/year). Import from any service is free and preserves all your tags, links, and metadata.