Software Alternatives, Accelerators & Startups

TheSecondBrain.dev VS ForthWrite

Compare TheSecondBrain.dev VS ForthWrite and see what are their differences

TheSecondBrain.dev logo TheSecondBrain.dev

One Brain. Everywhere you work. One memory for Claude, ChatGPT, Cursor and every AI tool you use. Runs in your own Cloudflare account. Open source.

ForthWrite logo ForthWrite

Email that sounds like you, and gets measurably more like you every week. Drafts in Gmail, Outlook, and the browser. Free to start.
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You use AI every day. A year of it should add up to something, and right now it doesn't. Every new chat starts from zero.

Second Brain is a memory layer that runs in your own Cloudflare account. Claude, ChatGPT, Cursor, Windsurf and any other MCP client read and write the same store, so what you work out in one tool is there in the next one.

Getting things in

  • Connect what you already use: Obsidian, Notion (email and calendar ship with 2.1)
  • Save in the moment: Chrome extension, iOS Shortcuts, CLI, REST /capture
  • Or just let the assistant store things as you talk, which is how most of it happens

Getting things back

Recall is semantic, not keyword. Memories link to each other, so a multi-hop search surfaces the reasoning behind a decision, not just the decision.

Entries carry a status (canonical, draft, deprecated) so an agent knows which version of a fact to trust.

Contradictions get flagged for a human to settle instead of quietly overwritten.

Where it lives

Your Cloudflare account: Workers, D1 and Vectorize.

Typical personal use sits inside Cloudflare's free tier. Open source on GitHub. No account with us, and nothing routes through our infrastructure.

Setup

Signed desktop app for Mac and Windows, one-click Cloudflare deploy, or clone the repo and run wrangler.

  • ForthWrite Landing Page
    Landing Page //
    2026-06-19
  • ForthWrite Dashboard
    Dashboard //
    2026-06-19
  • ForthWrite In Gmail
    In Gmail //
    2026-06-19
  • ForthWrite Pricing
    Pricing //
    2026-06-19

ForthWrite is an AI email writing assistant for Gmail and Outlook that learns your writing style from your real sent mail. The more you use it, the more it sounds like you. Get smart drafts in seconds, auto-draft replies before you open your inbox, and maintain your personal voice at scale. Free to start, no credit card required. Works inside Gmail and Outlook on the web.

How it works

ForthWrite captures your tone, sentence rhythm, and sign-offs from your actual sent emails, then uses that profile to generate drafts that match how you write, not a generic AI voice. Every draft you edit or send improves the model over time.

Key features

  • Auto-draft: replies waiting in Gmail before you open your inbox
  • Voice matching from your real sent mail, not templates
  • Recipient-aware drafts that adapt to who you are emailing
  • Prompt Lab for version-controlling and A/B testing your persona prompt
  • BYOK support: bring your own API key for Claude, OpenAI, Grok, Mistral, and more
  • Works in Gmail and Outlook on the web, plus a standalone browser widget
  • Training data export and full data portability

Who uses it

Professionals who send high volumes of relationship-critical email: lawyers, financial advisors, recruiters, account executives, founders, and anyone who wants their inbox handled without sounding like a chatbot wrote it.

Pricing

Free tier includes 10 drafts per week with no credit card required. Paid plans start at $12/month and include unlimited drafts, custom persona prompts, and auto-draft.

TheSecondBrain.dev

Pricing URL
-
$ Details
Platforms
-
Release Date
2026 May
Startup details
Country
United States
State
GA
Founder(s)
Rahil Pirani

ForthWrite

$ Details
freemium $12.0 / Monthly (Standard plan)
Platforms
Web
Release Date
2026 June
Startup details
Country
United States
State
California
City
San Diego
Founder(s)
Curtis Boortz
Employees
1 - 9

TheSecondBrain.dev features and specs

  • Works with
    Claude, ChatGPT, Cursor, Windsurf, Codex, any MCP client
  • Where it runs
    Your own Cloudflare account (Workers, D1, Vectorize)
  • Recall
    Semantic search with multi-hop graph expansion, not keyword
  • Memory Status
    Entries marked canonical, draft or deprecated so agents know what to trust
  • Contradiction Detection
    Conflicts are flagged for you to settle, never auto-overwritten
  • Capture methods
    Chrome extension, iOS Shortcuts, CLI, REST /capture, MCP tools
  • Integrations
    Obsidian, Notion (email and calendar ship with 2.1)
  • Setup
    Signed Mac and Windows installer, one-click Cloudflare deploy, or wrangler
  • Open Source
    Yes, github.com/rahilp/second-brain-cloudflare
  • Cost
    Typical personal use fits inside Cloudflare's free tier
  • Data Access
    No account with us, nothing routes through our infrastructure

ForthWrite features and specs

  • Voice Matching
    Learns from your real sent mail, not templates
  • Auto-draft replies
    Replies waiting in Gmail before you open your inbox
  • Batch-drafting
    Draft replies for your entire inbox with one click
  • Works in browser
    Gmail, Outlook, and web browsers
  • BYOK support
    Claude, OpenAI, Grok, Mistral, and more
  • Prompt Lab
    Version control and A/B test your persona prompt
  • Free tier
    10 drafts per week, no credit card required

Analysis of ForthWrite

Overall verdict

  • I don't have verified information about a product called ForthWrite (forthwrite.ai). I cannot confirm its features, quality, or reputation, so I'm unable to provide an accurate assessment of whether it's good.

Why this product is good

  • No reliable data available on this specific product in my knowledge base
  • This may be a newer product, a niche tool, or possibly a fictional/hypothetical name
  • Providing details without verified information could result in inaccurate or fabricated claims

Recommended for

  • Unable to determine without verified product information
  • Consider checking the official website, user reviews on platforms like G2 or Trustpilot, and independent tech review sites for accurate details

TheSecondBrain.dev videos

The Same Memory, Across Every Al Tool | Second Brain Demo

More videos:

  • Demo - How to Set Up Second Brain Desktop App in 2 Minutes

ForthWrite videos

No ForthWrite videos yet. You could help us improve this page by suggesting one.

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Category Popularity

0-100% (relative to TheSecondBrain.dev and ForthWrite)
AI Memory
100 100%
0% 0
Email
0 0%
100% 100
AI
100 100%
0% 0
Email Productivity
0 0%
100% 100

Questions & Answers

As answered by people managing TheSecondBrain.dev and ForthWrite.

Which are the primary technologies used for building your product?

TheSecondBrain.dev's answer

  • Cloudflare Workers โ€” runtime
  • Cloudflare D1 โ€” SQLite, entries and relationship graph
  • Cloudflare Vectorize โ€” embeddings and semantic recall
  • Workers AI โ€” embedding generation and synthesis
  • TypeScript
  • Model Context Protocol (MCP) โ€” client integrations
  • Tauri โ€” Mac and Windows desktop app
  • Wrangler + GitHub Actions โ€” deploy and release

ForthWrite's answer:

Next.js, React, Supabase, Anthropic Claude, OpenAI, Stripe, Vercel, Chrome Extensions API

What makes your product unique?

TheSecondBrain.dev's answer

Most AI memory tools store your context on their servers. This one deploys into your own Cloudflare account, so the memory is yours in a literal sense: your database, your vectors, your billing. We can't read it because we never have it.

The other difference is recall:

  • Semantic, not keyword. Ask by meaning, not by remembering what you called it.
  • Multi-hop. Memories link to each other, so a query surfaces the reasoning behind a decision, not just the decision.
  • Status-aware. Entries are marked canonical, draft or deprecated, so an agent knows which version of a fact to trust.
  • Honest about conflicts. When two memories disagree it flags it for you instead of quietly picking a winner.

ForthWrite's answer:

ForthWrite learns your writing style from your actual sent mail, not a generic prompt. Every draft sounds like you wrote it because it was trained on how you actually write. It also auto-drafts replies before you open your inbox, so your email is partially handled before your day starts.

Why should a person choose your product over its competitors?

TheSecondBrain.dev's answer

It works everywhere you work. Claude, ChatGPT, Cursor, Windsurf, Codex, any MCP client. Most memory tools only remember what happened inside their own app, so you end up with three AI tools holding three different versions of you.

You own the deployment. One-click deploy to Cloudflare, or a signed desktop installer if you'd rather not touch a terminal. Typical personal use sits inside Cloudflare's free tier, so there's no subscription to cancel and no vendor to migrate off later.

It's open source. MIT licensed. Read the code, fork it, extend it. Nothing about how your memory is stored or retrieved is a black box.

ForthWrite's answer:

Most AI email tools give you a blank box and a "write for me" button. ForthWrite builds a voice profile from your sent history and gets more accurate with every draft you edit or send. Unlike ChatGPT or Gemini, it works natively inside Gmail and Outlook with no copy-paste. Unlike Lavender, it writes the draft, not just scores it.

How would you describe the primary audience of your product?

TheSecondBrain.dev's answer

People who already live in these tools. They have an Obsidian vault or a Notion workspace, they're in Claude or ChatGPT every day, and some of them are in Cursor too. They're not casual users and they're not necessarily developers. They've built a system, and they've noticed the system doesn't talk to itself.

The shared frustration isn't "AI forgets." It's that a year of real thinking, hours of working through actual problems, hasn't left anything behind. Every conversation is good and then it's gone, and a month later they're figuring out the same thing from scratch.

They also tend to care where their work sits. Not privacy absolutists, just people who'd rather their own thinking accumulate in an account they control than in someone else's product they might have to leave.

ForthWrite's answer:

Professionals who send high volumes of relationship-critical email and cannot afford to sound generic: lawyers, financial advisors, recruiters, account executives, consultants, and founders managing their own inbox.

What's the story behind your product?

TheSecondBrain.dev's answer

I was using Claude, ChatGPT and Cursor every day and re-explaining the same projects to each of them. A year of that adds up to nothing. The decisions I'd worked out in one tool simply didn't exist in the next one.

I built it for myself first, on Cloudflare because I already had an account and the free tier meant I could run it without thinking about cost. Then I open sourced it, and what people asked for shaped what it became. The desktop app exists because a user on Product Hunt asked for a path that didn't involve a terminal, and she was right to ask.

I still use it every day. Most of the roadmap comes from hitting the limits of my own memory layer.

ForthWrite's answer:

Built out of frustration with AI writing tools that produce text that sounds nothing like the person sending it, and as a way to handle large amounts of daily email. The core insight was that your sent mail is the best training data you already have, and no tool was using it.

Who are some of the biggest customers of your product?

TheSecondBrain.dev's answer

  • People who run Obsidian, Notion and several AI tools side by side
  • Consultants, operators and independent professionals who think out loud with AI all day
  • Writers, researchers and strategists whose best thinking currently lives in chat logs they can't search

User comments

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Reviews

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TheSecondBrain.dev Reviews

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ForthWrite Reviews

  1. curtisboortz
    ยท Founder at ForthWrite ยท
    I built ForthWrite to fix generic AI email, and I still use it every day

    I built ForthWrite because I kept sending emails that sounded like they came from the same generic AI as everyone else. After launching it, I still use it for my own inbox every day, which is about the most honest endorsement I can give.

    The Chrome extension lives inside Gmail and Outlook on the web. Open a thread, hit Alt+Shift+D, and a draft comes back in your voice, not a template. The free tier is real: 10 drafts per week, no API key, no credit card. Voice matching is included on free, because that is the point.

    What keeps it useful compared to Gemini or a chat tab: it learns from what you actually send. Every edit you make before hitting send becomes a signal. Over time the drafts drift closer to how you really write, and the dashboard shows the improvement curve so you can see it happening.

    The web compose surface lets you draft from forthwrite.ai without installing anything, useful for people who want to try before committing to the extension.

    Standard adds recipient-aware and intent-aware drafting plus AI coaching. Pro adds auto-draft (replies waiting when you open Gmail), batch replies, and Prompt Lab for version-controlling your prompts. Teams adds a shared persona and seat-level analytics.

    ForthWrite is not for everyone. If you just need quick replies and tone does not matter, Gemini is free and already in your inbox. ForthWrite is for people where tone does matter: client communication, relationship-driven threads, external correspondence where sounding off costs something real.

    Disclosure: I am the founder and use it daily. Happy to answer questions in the comments.

    ๐Ÿ Competitors: Jace.ai, Fyxer, Mailmeteor
    ๐Ÿ‘ Pros:    Drafts land inside gmail and outlook; no copy-pasting from a chat window|Voice matching is on the free tier, not paywalled behind paid plans|No api key, no credit card to start; free tier runs on a server-side proxy|Learns from every edit you make before sending; drafts improve over time|Full keyboard flow: alt+shift+d to draft in any thread, no mouse required|Byok on paid plans, 9 providers supported, keys encrypted at rest|Web compose at forthwrite.ai works without installing the extension at all
    ๐Ÿ‘Ž Cons:    10 free drafts/week is enough to evaluate, not enough for a heavy inbox|Auto-draft, batch replies, and prompt lab all require the pro tier|Early-stage product; fewer third-party integrations than mature inbox tools|No mobile app: the extension and add-in are desktop-only (chrome on web, or the outlook desktop add-in)

What are some alternatives?

When comparing TheSecondBrain.dev and ForthWrite, you can also consider the following products

ChainMemory - Portable, verifiable memory for AI agents โ€” works across ChatGPT, Claude, Gemini and any MCP client

ReclaimAI - Helps users prioritize their work and personal calendars

Agentmemory - Persistent memory for Claude Code, Codex & coding agents

Superhuman - Superhuman is an email management tool.

OpenMemory MCP - Your private, local memory layer for all AI tools

Shortwave - Email smarter & faster with a reinvented experience for your Gmail