Cookie Policy | Mythos Docs

Mythos Software, LLC operates Mythos. This page explains what Mythos stores on your device, what each item does and how to manage it. For how we handle personal data more broadly, see the Privacy Policy.

The short version

The mythos.new app uses essential cookies and browser storage to keep you signed in, protect account-connection flows, and remember preferences. If you allow optional analytics, we use PostHog EU to understand product use. A separate session-replay choice allows sampled, masked recordings on a small set of public pages. Both choices are off until you consent, and Global Privacy Control blocks both. A live project with Visitor analytics enabled automatically uses a host-only 30-minute analytics session cookie unless a remembered refusal or Global Privacy Control blocks collection. Mythos does not add a consent card or preferences button. Existing preferences, and explicit choices made through a site-owned control, can be remembered for up to 180 days. We set no advertising cookies, third-party analytics cookies, or marketing tracking pixels.

Every item we store on your device is listed on this page, with its lifetime and what it is for.

Manage cookie preferences

What cookies are

Cookies are small text files a website stores on your device so it can remember things between requests — for example, that you are signed in. Cookies can be first-party (set by the site you are visiting) or third-party (set by another domain whose content is embedded in the page). Similar technologies such as localStorage, sessionStorage, and IndexedDB keep data in your browser without sending it to the server on every request. On this page “cookies” covers all of them, and the tables below list each type separately.

Cookies we set

The mythos.new app cookies in the first table support sign-in, security, and essential preferences. Remembering an analytics choice does not itself authorize analytics collection. The published-site table is separate: built-in analytics is controlled by the project owner and respects the host preference and Global Privacy Control described below. It never runs in Preview or while a project is unpublished.

Cookies set by the mythos.new app

Supabase session and PKCE cookie names may include -epoch-<random-id> after auth-token, before any numbered chunk or -code-verifier suffix. This random namespace separates sessions across an explicit sign-out.

Storage item	Duration	Purpose
`sb-…-auth-token`	Up to 400 days; refreshed while you use mythos, cleared on sign-out	Keeps you signed in — holds your Supabase Auth session used to authenticate every request. Large sessions may split into numbered chunks (…auth-token.0, .1).
`sb-…-auth-token-code-verifier`	Deleted when sign-in completes; an abandoned sign-in leaves it until its 400-day expiry	Security (PKCE) value proving the browser that finishes sign-in is the same one that started it.
`mythos-session-ended`	Up to 400 days; cleared after successful sign-in	Prevents a delayed request from restoring a session after sign-out. Contains only a sign-out marker.
`mythos-session-epoch`	Up to 400 days; replaced on the next explicit sign-out	Separates a new sign-in from delayed responses belonging to the previous session. Contains a random value, not an account identifier.
`sb_oauth_state, sb_oauth_pkce`	Legacy only; no longer created, and any existing value expires within 10 minutes	Temporary rolling-deploy compatibility for a Supabase connection started before the server-side OAuth transaction store was enabled.
`mythos_admin_sidebar_v1`	1 year; scoped to the /admin path	Super-admin only. Remembers whether the admin console’s navigation sidebar is collapsed so it renders the same way on your next visit. Set only for accounts with admin access.
`mythos-admin-language`	1 year; scoped to the app hostname	Remembers the admin console language selected by an administrator: American English or Russian.
`__Host-mythos_product_analytics`	30 days after a saved choice; cleared on explicit sign-out	A signed, random consent-subject identifier lets the app retrieve this browser’s analytics and replay choices. Host-only, Secure and HttpOnly; it does not contain prompts, profile details or credentials. Collection still requires a valid grant. Local HTTP development uses `mythos_product_analytics_local` instead.

Cookies on analytics-enabled published sites

Storage item	Duration	Purpose
`__Host-mythos_analytics_consent`	Up to 180 days after an explicit choice	Retains `v1.accepted` or `v1.rejected` on this published hostname, including a choice made through a site-owned control. A rejection stops collection. Contains no visitor identifier. The tracker does not write an accepted preference when this cookie is absent.
`__Host-mythos_analytics_session`	30 minutes after the most recent recorded page view	A random UUID groups page views into a pseudonymous visit while owner-enabled analytics is permitted by the current preference and Global Privacy Control. It is host-only, is not shared across domains, and is cleared when collection is blocked.

Public documentation at docs.mythos.new is hosted by Fern and can have provider-managed storage or security behavior; see Fern’s privacy notice. This inventory covers storage controlled by the Mythos app and built-in published-site analytics. Additional scripts that a project owner adds have their own purposes and controls. Hosted Stripe Checkout has Stripe’s own payment and security cookies; it is not controlled by the Mythos app preference panel.

mythos.new is served through Cloudflare, our CDN and security provider. Cloudflare may set its own strictly-necessary security cookies (such as __cf_bm) to distinguish humans from automated traffic; those are governed by Cloudflare’s privacy policy.

Browser storage we use

Beyond cookies, mythos uses localStorage for durable recovery and preferences, sessionStorage for tab-scoped recovery, and IndexedDB for attachment bodies that are too large for key-value storage. Names containing angle-bracket placeholders describe a key family rather than a literal key; for example, one owner-scoped key can be created for each account.

A record can reach its stated logical expiry and stop being read before the browser physically deletes its bytes. Where cleanup is best-effort, the duration row says so. You can remove all remaining records at any time by clearing site data for mythos.new.

localStorage keys set by mythos

Storage item	Duration	Purpose
`mythos:session-ending`	Replaced on the next sign-out or removed when site data is cleared	Notifies other open tabs that sign-out started or completed. Contains a random operation identifier and completion state.
`mythos_cookie_notice_ack_v1`	Until you clear browser storage	Remembers notice dismissal. A previous dismissal does not grant optional analytics or replay consent, and does not disable Cloudflare Web Analytics.
`mythos_posthog_consent_v1`	Until you clear browser storage or the SDK updates the preference	Stores only the PostHog SDK’s local allow/deny flag after a confirmed analytics choice. The SDK keeps its analytics identity and event state in memory, not persistent browser storage.
`mythos_analytics_withdrawn_v1`	Until a new analytics grant is confirmed or you clear browser storage	An immediate withdrawal marker stops collection in this browser and its other open tabs while the server records your choice. It contains no analytics identity or content.
`mythos_connectors_workspace_v1`	Until you choose a different workspace, clear the selection, or clear browser storage	Stores only the workspace ID last selected in the Connectors catalogue so the catalogue reopens on that workspace. The saved ID is ignored if the signed-in account can no longer access it.
`mythos_pending_prompt_v3`	Usable for up to 24 hours and cleared immediately after a durable owner-bound handoff claim is confirmed. Expired or invalid copies are ignored and may remain until you clear browser storage	Keeps the project prompt you typed on the landing page so it survives the sign-in redirect.
`mythos:guided-composer:v1`	Removed as soon as you submit or dismiss the draft; an abandoned draft remains until you clear browser storage	Holds the unsubmitted answers of the guided page title, description or favicon form — the project it belongs to, the version of your code it was prepared against, and the wording you chose — so the form survives a reload before you submit it.
`keek_pending_prompt`	Legacy only; no longer read or created. Removed when the current prompt flow next accesses browser storage, or when you clear browser storage	Retired landing-prompt key kept only in cleanup code so a cached pre-owner-binding app version cannot pass its value into the current protocol.
`mythos_post_auth_prompt_handoff_durable_v2`	Usable for up to 15 minutes. The first signed-in account claims it under a browser lock; it is cleared only after exact project-success settlement. Expired or invalid copies are ignored and may remain until you clear browser storage	Paired durable copy of the post-sign-in prompt handoff. It is reconciled with the tab copy so a partial owner claim cannot expose the prompt to another account.
`mythos_post_auth_prompt_handoff_owner`	Usable for up to 15 minutes. Cleared with the exact prompt handoff after project creation or during a later expired-handoff cleanup; otherwise it remains until you clear browser storage	Stores only the signed-in account ID and opaque handoff ID (not the prompt) so an interrupted dashboard navigation can rediscover that account’s owner-bound prompt.
`mythos_post_auth_prompt_handoff_durable`	Legacy only; no longer read or created. Removed when the current prompt flow next accesses browser storage, or when you clear browser storage	Retired durable handoff key retained only for rolling-deploy cleanup. Current handoffs use an isolated versioned key.
`mythos_pending_remix`	A pre-submit choice is usable for up to 15 minutes; a submitted operation normally for up to 24 hours. A server-requested wait can retain the submitted record until that wait ends plus 2 minutes, never beyond 48 hours 2 minutes from the original save. Cleared after creation, insufficient-credit settlement, or terminal failure; expired or invalid copies are ignored and may remain until you clear browser storage	Remembers the template remix choice and, after submission, the exact idempotent operation so an interrupted request can be reconciled safely.
`keek_pending_referral`	Cleared after the referral is accepted or definitively rejected. Network errors and explicitly temporary outages keep it for a later sign-in retry; otherwise it remains until you clear browser storage	Stores the referral code from a link you followed so the person who invited you can be credited.
`mythos_pending_blank_project:<account-id>`	Normally usable for up to 24 hours. A server-requested wait can retain it until that wait ends plus 2 minutes, never beyond 48 hours 2 minutes from the original save. Cleared after the project is created or converted into a terminal-failure record; expired or invalid copies are ignored and may remain until exact cleanup or you clear browser storage	One owner-scoped recovery record per signed-in account for an interrupted blank-project creation, including the prompt, template, attachment digest, and idempotency identity.
`mythos_pending_blank_project_failure:<account-id>`	Usable for up to 24 hours. Cleared when the exact failure is dismissed or superseded by a successful retry; expired or invalid owner records are removed during later recovery when browser storage is available	One owner-scoped terminal-failure notice per account so a failed project request can be shown or retried without exposing another account’s draft.
`mythos_pending_blank_project`	Rolling-deploy compatibility only. A saved intent follows the same bounded wait as the account-scoped record: normally 24 hours, at most 48 hours 2 minutes. A safety marker remains usable for no more than 24 hours; stale copies are ignored and may remain until a later compatibility write or you clear browser storage	Legacy singleton retained temporarily as a fail-closed migration fence while blank-project recovery moves to owner-scoped keys.
`mythos.pending-attachments.v1.<account-id>.<project-id>`	Ready metadata is usable for up to 24 hours. Acknowledgement or expiry replaces it with a small consumed or unavailable marker; terminal project failure deletes it. A marker can otherwise remain until you clear browser storage	Metadata only for an attachment handoff: account and project IDs, timestamps, item count, status, and a payload fingerprint. Attachment bodies are kept separately in IndexedDB.
`mythos:admin-credit-adjust:<account-id>`	No fixed expiry. Cleared after confirmed success or a known terminal rejection; an outcome-unknown operation is kept for exact replay until an administrator reconciles it or clears browser storage	Super-admin only. Preserves an idempotent credit adjustment, including its account, amount, reason, and operation key, across reloads.

sessionStorage keys set by mythos

Storage item	Duration	Purpose
`mythos:sign-out-notice`	Removed after the notice is read or the tab session ends	Records only that sign-out on other devices could not be confirmed, so the next page can explain the outcome.
`mythos.share-preview.token.v1`	Until the browser tab is closed or you clear site data; an expired or revoked Share Preview token is rejected by the server	Share Preview only. Keeps the bearer token in the current tab after removing it from the address bar so the shared preview can continue to load.
`mythos.project-presence.session.v1:<project-id>`	Until the browser tab is closed or you clear site data; a new tab receives a different random value	Keeps one random tab-session UUID per open project so presence heartbeats can be retried without creating duplicate sessions. It contains no location, activity history, or last-editor identity.
`mythos.pendingPeopleInvitationToken`	Until the invitation is accepted or the browser tab is closed; removed as soon as it has been used	Holds a workspace invitation token across the sign-in redirect, so opening an invitation link while signed out still joins the right workspace after you sign in.
`mythos_post_auth_prompt_handoff_v2`	Usable for up to 15 minutes. The first signed-in account claims it under a browser lock; it is cleared only after exact project-success settlement or when the tab session ends. Expired or invalid copies are ignored	Tab-scoped half of the owner-bound landing-page prompt handoff. It must agree with the durable copy before the prompt is shown.
`mythos_post_auth_prompt_handoff`	Legacy only; no longer read or created. Removed when the current prompt flow next accesses this tab, or when the tab session ends	Retired tab handoff key retained only for rolling-deploy cleanup. A server protocol fence strips handoff nonces emitted by cached app versions.
`mythos:room:v1:<account-id>:<project-id>`	Usable for up to 24 hours after its last update within the current tab. Removed when empty, explicitly cleared or found expired; otherwise retained until the tab closes or site data is cleared	Recovers an unsent Room message, attachment metadata, reply context and pending message identities for that account and project.
`mythos:file-drafts:v1:<account-id>:<project-id>`	Until the saved edits or pending operation are cleared, you sign out, the tab closes or site data is cleared	Recovers unsaved editor file contents and their base contents. Related keys with `:pending`, `:build-source-target` or `:accept:<draft-id>:<revision>` suffixes retain Draft creation, the selected Build target and exact acceptance identities across reloads.
`mythos:queued-messages:<account-id>:<project-id>`	Until the saved instruction is acknowledged or removed, the tab closes or site data is cleared	Recovers queued Build or Plan instructions, attachment metadata and the identity of an unconfirmed submission without submitting it as a new operation.
`mythos:question-draft`	No fixed expiry within the tab session. The app attempts removal after confirmed submission or Skip all, or when a check of that round confirms its questions ended or changed; otherwise until the tab session ends or site data is cleared. Sign-out does not clear these drafts.	Recovers unfinished Build answers, selected options and the current question across reloads. Keys are JSON-encoded arrays identifying the account, project, Build, assistant message and exact question offer.
`mythos:plan-question-draft`	No fixed expiry within the tab session. The app attempts removal after confirmed acceptance of answers or Skip all; otherwise until the tab session ends or site data is cleared. Changing the question round or signing out does not clear older drafts.	Recovers unfinished Plan answers, selected options and the current question across reloads. Keys are JSON-encoded arrays identifying the account, project, Plan session and exact question round, including question text and choice metadata.
`mythos.email-otp.v1`	Usable for up to 15 minutes; cleared after successful sign-in, when reset or found expired, or when the tab closes	Keeps the email address and send/resend timestamps for an unfinished email-code sign-in. It stores no one-time code, access token or session.

IndexedDB storage used by mythos

Storage item	Duration	Purpose
`mythos-local-handoffs / pending_generation_inputs`	Until exact server acceptance, explicit discard after a known terminal outcome, or site-data deletion; unknown outcomes retain the bytes	Stores exact text, attachment bodies and operation identities for instructions submitted during a Build. Opening the same account/project can recover these records even after the tab index is lost, without submitting a new instruction.
`mythos-local-handoffs / pending_attachments`	Attachment bodies are usable for up to 24 hours and are removed after exact server acknowledgement, terminal project-create failure, expiry cleanup, or when you clear browser storage	IndexedDB database and object store holding attachment bodies and integrity metadata while an interrupted first project creation is safely handed to the server.

Analytics, advertising, and error monitoring

We use no Google Analytics, Plausible or advertising trackers. Optional product analytics and session replay are separate from essential monitoring and customer-published-site analytics:

Optional product analytics (PostHog EU) — if you consent, bounded events describe sign-up, page categories, template selection, Builds, previews, publishing, connectors and purchases. These events use opaque account/project identifiers and limited outcomes, counts, timings and amounts. They exclude email addresses, prompts, chat, code, attachments, credentials and private URLs. The browser SDK loads only on the public homepage, pricing page and template catalogue, without a query string or fragment. Product events from other app surfaces are sent through Mythos’s server only after valid analytics consent. We do not inject PostHog into customer-built sites.
Optional session replay and heatmaps (PostHog EU) — require both analytics consent and a separate replay choice. Recordings are sampled and limited to those public pages without queries or fragments. Text and input values are masked; form controls, media and embedded previews are blocked. Authentication, dashboards, workspaces, chat, code, Preview, payment, settings and admin surfaces are excluded. Network bodies, headers and console content are not recorded.
Cloudflare Web Analytics — public mythos.new pages send a cookieless browser beacon to Cloudflare to measure visits and page performance. This is separate from visitor analytics on published projects. Dismissing the Mythos app cookie notice does not disable this beacon. See Cloudflare’s data collection documentation.
Performance and error beacons — technical reports (page timing, a JavaScript error) posted to our own endpoints to keep the product fast and working.
Error monitoring (Sentry) — when something breaks, a scrubbed technical error report is delivered to Sentry’s EU service, including through Mythos’s same-origin monitoring tunnel so we can fix it. The Sentry browser SDK sets no cookies here, session replay is disabled, and reports do not include personal data by default.
Published-site Visitor analytics — runs automatically on a live published project whose owner leaves the setting enabled, unless the current host preference or Global Privacy Control blocks it. A first-party script uses the __Host-mythos_analytics_session cookie above to group page views into a 30-minute visit. It records only a query-free pathname, referrer hostname or Direct, coarse device class, and country code. It does not retain IP, full user-agent, full referrer, query parameters, a fingerprint, or a cross-visit profile.

Managing cookies

The Manage cookie preferences button above opens the Mythos app’s essential-storage information and separate analytics and replay choices. You can reject or withdraw either optional choice without losing access to the service. While signed out, your choice applies to this browser; while signed in, it applies to your account. A valid browser choice can carry into an account with no saved choice, but cannot replace an existing refusal. Signing out stops the SDK and clears its current identity. Global Privacy Control overrides a saved grant and stops both optional analytics and replay. Withdrawal stops new collection; contact us for deletion of previously collected data. It does not disable cookieless Cloudflare Web Analytics or control a different hostname. Published sites do not receive a Mythos-injected preferences control. Built-in analytics respects an existing host-scoped rejection and Global Privacy Control; either stops new events and clears the session cookie. Site owners can supply a control that records an allow/reject preference. An unrecognized or duplicate host preference, or unavailable browser cookie storage, blocks collection. Old unprefixed analytics cookies are ignored and are not upgraded.

Project owners can stop new visitor events under More → Project settings → Publishing → Visitor analytics. Owners remain responsible for the notices and consent required for their application, including built-in analytics. Where prior consent is required, their site must set the host preference to rejected before the analytics script executes, then update that preference after an explicit choice. This control does not manage additional analytics, embeds or other code an owner adds.

Your browser also lets you inspect, delete, or block cookies for any site. Clearing mythos.new app cookies signs you out. Clearing only an analytics session cookie can start a new pseudonymous session if collection remains enabled and is not blocked by your preference or Global Privacy Control. Clearing or letting a rejection preference expire can allow automatic collection to resume; deleting that preference is not a persistent opt-out. Cookie settings are per hostname, device, and browser.

We do not sell or share personal data for cross-context behavioral advertising. Built-in published-site analytics honors Global Privacy Control by stopping collection, including when a stored preference says accepted. Global Privacy Control also stops optional Mythos product analytics and replay.

Changes and contact

If we add a cookie or storage key, change a lifetime, or introduce a third party that can set cookies, we will update this page and the date shown above.

Mythos Software, LLC — 2810 North Church Street, STE 90672, Wilmington, DE 19802, United States.

Questions about our use of cookies: privacy@mythos.new.