Terms of Service · Substack Notes MCP
On this page
- 1. Agreement
- 2. What this product is
- 3. Unofficial API disclaimer — USE AT YOUR OWN RISK
- 4. Subscription gate & access eligibility
- 5. Payment and refunds
- 6. Bring-your-own-key (BYOK) session cookie
- 7. Tool output
- 8. Acceptable use
- 9. Service availability
- 10. Disconnecting & deletion
- 11. Support
- 12. Conflict with Master Terms
1. Agreement
These product-specific Terms of Service govern your access to and use of the Substack Notes MCP at substackmcp.genaiunplugged.com. They are supplemental to and governed by the GenAI Unplugged Terms of Service (the "Master Terms"), which cover disclaimers of warranties, limitation of liability, indemnification, intellectual property, governing law (Commonwealth of Pennsylvania), and dispute resolution (30-day informal period, then binding arbitration, class action waiver). By authenticating or using the Substack Notes MCP you agree to both documents. In the event of any conflict, the Master Terms control.
2. What this product is
The Substack Notes MCP is a Model Context Protocol (MCP) server operated by GENAI UNPLUGGED LLC. It enables compatible AI clients — including Claude Desktop, Claude Cowork, and Claude Code — to schedule Substack Notes, publish Notes, manage drafts, and retrieve basic publication analytics on your behalf using your own Substack session cookie. The server is hosted on Cloudflare Workers at substackmcp.genaiunplugged.com, with OAuth authentication flows running on Oracle Cloud infrastructure at www.genaiunplugged.com.
The Substack Notes MCP is a service, not a downloadable product. You receive access, not a transferable license. GENAI UNPLUGGED LLC controls, operates, and is solely responsible for the service. There is no co-brand partner. This product is not affiliated with, endorsed by, or approved by Substack, Inc. in any way.
3. Unofficial API disclaimer — USE AT YOUR OWN RISK
⚠️ IMPORTANT — READ CAREFULLY BEFORE USING
Substack has no official public API. The Substack Notes MCP operates by sending HTTP requests to Substack's internal (private, undocumented) endpoints using your own session cookie. These endpoints are not designed or intended for third-party programmatic access.
Use of this tool may violate Substack's Terms of Service. Substack's Terms of Service (substack.com/tos) prohibit automated access to their platform without express written permission. By using this MCP, you assume all risk of account suspension, content removal, or other consequences imposed by Substack.
GENAI UNPLUGGED LLC assumes no liability for any action taken by Substack against your account as a result of using this tool, including but not limited to account suspension, data loss, or loss of paid subscriptions. You agree that YOU USE THIS TOOL AT YOUR OWN RISK.
By using the Substack Notes MCP you confirm that: (a) you have read and understood Substack's Terms of Service; (b) you accept all risk of violating those terms; and (c) you will not hold GENAI UNPLUGGED LLC responsible for any consequences arising from your use.
4. Subscription gate and access eligibility
Access to the Substack Notes MCP requires an active GenAI Unplugged Substack subscription:
- Free tier: available to any active GenAI Unplugged Substack subscriber (free or paid). Includes Notes management (6 tools), basic analytics (2 tools), and post listing. No credit card required with us.
- PluggedIn (Paid) tier: requires an active GenAI Unplugged paid Substack subscription. Unlocks advanced analytics tools (subscriber growth timeseries, per-post traffic stats). Pricing is managed by Substack, not by us.
"Active" means your subscription has not been cancelled, lapsed, or suspended on Substack at the time of the access request. Access auto-revokes when your subscription lapses. You may not share, sell, or transfer your access tokens or session credentials.
5. Payment and refunds
We do not process payments for the Substack Notes MCP directly. Subscription payments are collected and managed by Substack under Substack's own billing terms. Refund requests for the Substack subscription are governed by Substack's refund policy. For billing disputes related to GenAI Unplugged, contact support@genaiunplugged.com.
6. Bring-your-own-key (BYOK) — Substack session cookie
To use the Substack tools, you must provide your own Substack session cookie via the X-BYOK-Substack-Cookie HTTP request header. This is a BYOK arrangement: the cookie is yours, and it is handled as follows:
- We never store your session cookie. The value travels in the request header, is forwarded once to Substack's endpoints in the same request lifecycle, and is then dropped from memory. It is never written to logs, databases, or any persistent storage.
- You are solely responsible for keeping your session cookie confidential. Do not share your cookie in public configs, screenshots, or version-controlled files.
- Cookie expiry: Substack session cookies typically expire within 30 days or when you log out of Substack in your browser. When a cookie expires, Substack tool calls will return authentication errors. You must obtain a fresh cookie from your browser and update your config.
- Rate limits: 50 tool calls per hour and 200 tool calls per day per authenticated user, applied across all Substack tools. These limits are a protective cap, not a contractual SLA. GENAI UNPLUGGED LLC may adjust limits at any time.
7. Tool output
The tools provided by the Substack Notes MCP interact directly with your Substack account. Actions such as publishing or scheduling Notes are irreversible once confirmed by Substack. You are solely responsible for reviewing tool output and confirming actions before they are executed. GENAI UNPLUGGED LLC is not responsible for unintended publications, incorrect scheduling, or data loss resulting from tool use.
8. Acceptable use
In addition to the prohibited-use rules in the Master Terms, you may not:
- Use the Substack Notes MCP to publish spam, misleading content, or content that violates Substack's content policies or applicable law.
- Use the service to make automated, scripted, or bulk tool calls beyond the rate limits in Section 6.
- Attempt to reverse-engineer, scrape, or extract internal API endpoints, tool definitions, or session management logic.
- Share your OAuth access tokens, refresh tokens, or Substack session cookie with any other person or system.
- Use the service in any way that violates the Terms of Service of your AI client (Claude Desktop, Claude Cowork, Claude Code, etc.).
- Use the service to access a Substack account that does not belong to you.
9. Service availability
The Substack Notes MCP is provided on an "as-is" and "as-available" basis. We may modify, rate-limit, suspend, or discontinue the service or any tool at any time without prior notice. We are also subject to changes or disruptions in Substack's internal API; Substack may block, change, or remove API endpoints at any time, and GENAI UNPLUGGED LLC is not responsible for service disruption resulting from Substack's actions. Planned maintenance will be communicated via the GenAI Unplugged Substack on a best-effort basis.
10. Disconnecting and account deletion
You can revoke your OAuth tokens at any time by re-authenticating with a new magic link or by contacting support. Disconnecting does not cancel your Substack subscription; manage that directly on Substack.
To request deletion of all data we hold about you (OAuth token records, KV entries, audit log rows), email support@genaiunplugged.com. We will action deletion requests within 30 days. The 90-day audit log auto-purges in any case. We do not hold your Substack session cookie.
11. Support
Questions, issues, and bug reports: support@genaiunplugged.com. We aim to respond within 3 business days on a best-effort basis. We cannot guarantee resolution of issues caused by Substack's internal API changes or your MCP client's behaviour.
12. Conflict with Master Terms
Nothing in these product Terms expands, reduces, or overrides the GenAI Unplugged Master Terms. If any provision here conflicts with the Master Terms, the Master Terms control. The unofficial-API disclaimer and "use at your own risk" language in Section 3 are additive — they do not reduce the protections afforded to GENAI UNPLUGGED LLC under the Master Terms.