xmark lets you chat with your X (Twitter) bookmarks. you sign in, connect your X account, sync your bookmarks, and ask questions in plain english. xmark uses semantic search over the full bookmark contents (text, quoted tweets, linked articles, image alt text) to answer.

go to /auth/signup and sign in with Google. once you're in, head to /bookmarks and connect your X account via the 'connect' button. xmark uses two separate OAuth flows: Google for the xmark account itself, X for read access to your bookmarks.

do I need an X (Twitter) account?

yes. xmark reads your X bookmarks via the X API, so you need an X account with bookmarks already saved. if you've never bookmarked anything on X, there's nothing for xmark to chat with.

xmark is a single $5/month plan. no free tier, no upgrades. one price covers unlimited bookmark sync, unlimited chat messages, and access to all features.

how do I sync my bookmarks?

open /bookmarks and click 'sync'. xmark pulls your bookmarks from X via the X API and embeds new ones with OpenAI's text-embedding-3-small for semantic search. the first sync may take a minute if you have hundreds of bookmarks; subsequent syncs only process new ones.

no. sync is manual — you click the button when you want fresh bookmarks. this keeps API usage predictable and avoids hitting X's rate limits unnecessarily.

the full tweet text (including long-form note tweets), author info, engagement metrics, quoted tweets, image alt text, linked article metadata (title + description), and topic annotations. all of this becomes searchable in chat.

X says my account 'needs to be reconnected' — what now?

X's OAuth tokens expire and rotate. when xmark can't refresh your token, you'll see a 'reconnect' prompt on /bookmarks or /settings. click reconnect to re-authorize. xmark detects rotated refresh tokens and saves them automatically going forward.

can I delete a bookmark?

yes. clicking the remove icon on a bookmark unbookmarks it on X AND removes it from xmark in one step. both must succeed — leaving X bookmarked while removing locally would let the next sync re-create it.

you ask a question, xmark embeds it with OpenAI, retrieves the most relevant bookmarks via pgvector cosine similarity, then asks Claude (claude-sonnet-4-5) to answer using those bookmarks as context. responses cite each bookmark by number — [1], [2] — so you can click through to the original tweet.

how many bookmarks does chat consider?

chat retrieves up to 800 of your most relevant bookmarks per query, ranked by semantic similarity to your question. if you have more, the lowest-ranked are excluded for that specific query, not deleted.

why is chat citing the same tweet multiple times?

Claude is told to cite every bookmark it references with a number. if a single bookmark is the best match for several parts of an answer, you'll see the same number repeated. clicking any instance of [N] opens the original tweet.

do you train models on my bookmarks?

no. your bookmarks are sent to OpenAI for embeddings (one-shot, not retained per OpenAI's API terms) and to Anthropic for chat answers (one-shot, not retained per Anthropic's API terms). xmark stores embeddings + bookmark text in your private Supabase row, gated by row-level security.

where is my data stored?

in xmark's Supabase Postgres database, encrypted at rest. row-level security policies ensure only your authenticated session can read your bookmarks and conversations. nobody else — no admin, no other user — can see your data.

what happens to my X access token?

X tokens are encrypted with AES-256-GCM before being written to the database. only the running app can decrypt them; database backups don't expose plaintext tokens.

how do I delete my account?

go to /settings and click 'delete account'. xmark soft-deletes your profile + bookmarks + conversations and hard-deletes your active credentials (X OAuth tokens, API keys). signing back in within the retention window restores your account; after that, the soft-deleted rows are purged.

what does the $5/month plan include?

unlimited bookmark sync, unlimited chat messages, full access to every feature. the plan is the only paid tier — there are no upsells or per-message overages.

go to /settings → billing and click 'manage subscription'. you'll be redirected to Stripe's customer portal where you can cancel at the end of the current period. cancellation stops the next charge; you keep access until the period ends.

do you offer refunds?

if you cancel within the first 7 days of a new subscription, email josh@jclvsh.art and we'll refund your most recent payment. after that, cancellations stop future charges but the current period isn't refunded.

sync is stuck or won't start

xmark uses a Redis lock to prevent concurrent syncs for the same account. if a previous sync hung, the lock auto-expires after 30 seconds — wait, then click sync again. if it still won't start, your X token may have expired (see the reconnect prompt).

chat says 'subscription required' but I just paid

Stripe webhooks usually arrive within seconds of checkout, but rarely take a minute. refresh /chat after 60 seconds; if you still see the message, contact support with your Stripe email and we'll reconcile the subscription manually.

I'm getting rate-limited by X

xmark uses X's pay-per-use API tier with strict rate limits. if you hammer the sync button or run many parallel sessions, X may briefly 429 you. wait a few minutes and try again. xmark treats 429 as 'X is healthy, just busy' — it's not a permanent error.

guides

beginnertrust4 minutes

privacy & data: where your bookmarks live

Where xmark stores your data, who can see it, what we do with embeddings, and how to delete everything.

steps

your bookmarks are yours

xmark stores your bookmarks in Supabase Postgres with row-level security (RLS). Every query is scoped to your user ID. Other users — and our service role itself, except for explicit admin operations — cannot read your data.

embeddings stay with us

We embed your bookmark text with OpenAI's text-embedding-3-small. The embedding API call is stateless: OpenAI receives the text, returns the vector, and (per their API policy) does not train on it. The vectors are stored in your row, alongside the bookmark.

chat answers stay with us

Chat uses Claude (Anthropic). The conversation history is stored in your account so you can come back to it. Same RLS — only you see your conversations. We don't share or sell prompts, answers, or bookmarks.

deletion is fast and complete

Settings → Danger zone → Delete account. We hard-delete credentials (X OAuth tokens, API keys, webhook secrets) immediately, soft-delete the profile (so the account ID stays unique), and purge data on a scheduled job. /data-deletion has the formal policy.

If you want xmark to forget without deleting your account — disconnect X. The OAuth token is hard-deleted on disconnect; subsequent syncs return zero.

ready to get started?

get started free sign in