Frequently asked questions

Hosted ($5/mo) is a single-tenant plan for one person. You get one memory store with one login, and every AI tool you use — ChatGPT, Claude, Cursor, custom scripts — writes into that same store. There are no per-agent fees.

Enterprise ($49/mo with one seat included; additional seats $9.99/mo each) is built for a team or department. Each Enterprise subscription is its own isolated tenant. If Engineering and Marketing need separate memory workspaces, they each get their own Enterprise subscription. See Pricing for full caps.

An agent is any software that makes API calls into your tenant — a ChatGPT conversation, a Claude session, a Cursor plugin, a LangChain script, a cron job, a sub-agent, anything. Agents are not billed separately on any plan. All plans include unlimited agents. See the formal definition in our Terms.

Yes. Upgrades and downgrades are handled through the Stripe Customer Portal — the link is in your welcome email and on the dashboard. Changes take effect at the next billing cycle. You will not lose any stored data when changing plans.

Requests that exceed a rate limit receive an HTTP 429 response immediately. If you approach your storage or monthly operation cap, you will receive a notification before your account is blocked. You will have 30 days notice before any overage charges take effect. See the Pricing page for full fair-use policy details.

The Hosted plan includes a 7-day free trial, then costs $5/month. There is no ongoing free hosted tier. See Pricing for the trial and plan details. The public reference implementation is separate from the current hosted service; review its documentation before considering a deployment of your own.

You do. Your data lives in your tenant, isolated from all other tenants. HeurChain does not mine your stored vectors for training data, does not share them with model providers, and does not index them for any other customer's queries. See our Privacy Policy for the full details.

From the dashboard, use "Download vault" to export your vault as a ZIP of Markdown files. The export includes both active working memory and vaulted records; no flush is needed before downloading.

Our Terms of Service provide for 30 days of data retention after your subscription ends, followed by permanent deletion. Export your data before cancelling if you need to keep it. The terms also explain cancellation and refund details.

No. Your stored vectors are never used to train HeurChain's own systems or any third-party AI model. Your tenant is isolated at the storage layer — other tenants cannot read your data, and HeurChain does not pass it to any model provider. See Privacy Policy section 3 for the formal statement.

HeurChain runs on Hetzner infrastructure in Falkenstein, Germany, with Cloudflare in front. Data is stored in the EU. A US region is planned. Enterprise Custom customers can discuss data residency requirements directly with sales.

A tenant is an isolated data silo — its own vector memory store, API key, and vault directory. Nothing written to your tenant is ever visible to any other tenant. On the Hosted plan you have one. On Enterprise, each subscription creates one. The formal definition is in Terms of Service section 5.

A seat is a human user account — one login attached to a tenant. Each seat represents one person who can access the tenant's dashboard, manage settings, and rotate the API key. Hosted includes one seat. Enterprise includes one seat and allows additional seats at $9.99/month each.

An agent is any software making API calls into a tenant — a ChatGPT conversation, a Claude session, a Cursor coding agent, a LangChain pipeline, a custom cron job. Agents are not billed separately on any plan. All plans include unlimited agents.

Unlimited agents can connect to your tenant, within the plan's storage, operation, and rate limits. You pay $5/month for the Hosted plan with one tenant and one human seat; there are no per-agent fees. See Docs for connecting your tools.

Yes, on Enterprise. The Enterprise plan is designed for this: the base subscription includes one seat, and you add teammates at $9.99/seat/month. All seats write into the same shared tenant. If two teams need separate siloed memory, each team buys its own Enterprise subscription — each gets its own isolated tenant.

Compatibility depends on the client, not just the model. HeurChain provides REST and MCP connections. API-key clients use X-HeurChain-API-Key and X-HeurChain-Tenant headers. OAuth-capable MCP clients use https://api.heurchain.com/mcp/sse and authorize workspace access separately from website sign-in. Gemini CLI supports SSE and custom headers; Gemini web/mobile Connected Apps requires OAuth. Hosted MCP OAuth is enabled and initial connectivity has been verified. Full refresh/revoke/reconnect and Gemini web/mobile compatibility remain unverified. An API key is not an OAuth Client secret. See Docs for connection instructions.

For a supported MCP client, start with the connection instructions in Docs. Choose API-key setup (SSE with API-key and tenant headers, or authenticated REST) or the OAuth connection flow offered by your MCP client. Website Google/GitHub sign-in alone does not grant an MCP app access. Custom application integrations and operating the public reference implementation require development or infrastructure experience.

The hosted service provides a REST API and MCP tools. Start with the current Docs for supported routes, authentication, and client setup. Examples in the public reference repository may differ from the hosted API.

A public reference implementation is available to inspect. It is separate from the current hosted service. Check the repository's license, dependencies, setup instructions, and suitability for your requirements before attempting to self-host. It is not a qualified release of the hosted service.

Not with a native plugin today, but Obsidian notes can be imported into your tenant via the HTTP API or via a script that reads your vault directory. Because HeurChain returns memory in readable text, you can also export your tenant and import it back into Obsidian. A dedicated Obsidian plugin is on the roadmap.

Yes. Data is encrypted in transit with TLS. Data at rest is encrypted with AES-256 at the storage layer. Enterprise Custom plans can discuss per-tenant key management. See our Privacy Policy for the full security statement.

Nobody under normal circumstances. Your tenant is isolated at the storage layer. HeurChain staff can access raw infrastructure for maintenance and incident response, but tenant data is never accessed for business purposes. We do not share your data with model providers, advertisers, or third parties. See Privacy Policy section 3.

Not yet. We are a small, early-stage company. SOC 2 Type II is on our security roadmap, but we do not have a timeline to share publicly. We will not claim certifications we do not hold. If you require SOC 2 or ISO 27001 as a procurement requirement, Enterprise Custom is the right conversation — email [email protected].

Email [email protected] with a description of the issue. Please do not disclose vulnerabilities publicly before we have had a chance to investigate and respond. We aim to acknowledge all security reports within 48 hours.

You can inspect a public reference implementation on GitHub. It represents earlier work and is separate from the current hosted service. Consult that repository for its license and supported setup; the public code should not be treated as the source of the current hosted deployment.