Milestone by Ouroboros Apps
Integrates with Stripe for subscription billing, including checkout with monthly/yearly billing intervals, payment terms, webhook handling, and subscription status checks that gate access to Milestone tools.
Integrates with Supabase for OAuth authentication and dynamic client registration, using the configured Supabase URL and anon key to sign in users and authorize MCP tool calls.
Milestone
Milestone keeps a freelancer's approved milestone definitions and what done means, then lets an assistant read that record before it answers. An assistant cannot say a milestone is complete, or that the next payment is released, unless the saved acceptance criteria were met. It cannot invent an extra deliverable or mark work done that was not saved.
It works with ChatGPT, Claude, Gemini, Grok, and Cursor, plus any other MCP client that can do Streamable HTTP and OAuth. It is not a ChatGPT-only plugin.
Sign in with your Milestone account when the assistant opens OAuth. Do not paste an API key or password into a header. Milestone supports dynamic client registration: leave the client id and secret empty. The protected-resource metadata at /.well-known/oauth-protected-resource/mcp points clients at the OAuth issuer, which registers them.
Milestone tools need Pro or an active trial. A new subscription includes a 14-day trial. This page does not list a price. Checkout shows the billing interval and payment terms.
To self-host, run the server and use the base URL you configure. The default MCP address is http://127.0.0.1:3000/mcp.
Hosted server
MCP server URL:
https://milestone-continuity2.vercel.app/mcp(Streamable HTTP, OAuth sign-in)Status: early access. Paste the URL into Claude, Cursor, Grok, or ChatGPT developer mode.
Registry name:
io.github.LAHutchins91/milestone
Related MCP server: Scope by Ouroboros Apps
What the assistant can do
After you approve the connection, the server exposes these tools:
list_milestone_sets
open_milestone_set
read_milestone_set
define_milestone
save_acceptance_criterion
save_deliverable
save_work_item
record_criterion_met
declare_milestone_complete
declare_next_payment_released
mark_work_done
write_client_wording
approve_milestones
suggest_milestone_change
accept_milestone_change
read_milestone_set is the read the assistant should do before it answers. It includes the milestone definitions, the acceptance criteria that say what done means, the saved deliverables and work, and what the assistant may tell the client. Draft definitions are not an approved commitment. A suggested milestone change does not change the record. After the milestones are approved, declare_milestone_complete refuses to call a milestone complete and declare_next_payment_released refuses to say the next payment is released unless every saved acceptance criterion on that milestone was met. save_deliverable refuses an extra deliverable, and mark_work_done refuses work that was not saved. Those additions go through suggest_milestone_change and then accept_milestone_change, and only when you explicitly approve that change.
The assistant only calls these tools when you and the host allow it.
Connect
Cursor, in ~/.cursor/mcp.json or a project .cursor/mcp.json:
{
"mcpServers": {
"milestone": {
"url": "http://127.0.0.1:3000/mcp"
}
}
}Do not add a headers block. Cursor registers a client and opens sign-in.
Claude Code:
claude mcp add --transport http milestone http://127.0.0.1:3000/mcpDo not pass an Authorization header. Other clients use the same address, choose OAuth, and leave client id and secret empty. Steps for ChatGPT, Claude, Gemini, Grok, and Cursor are on the connect page at /connect.
Registry metadata for this server is in server.json (io.github.LAHutchins91/milestone). The public remote MCP URL there is https://milestone-continuity2.vercel.app/mcp.
Run
npm install
npm test
npm run typecheck
npm run build
npm startWhen stdin is a terminal, Milestone serves Streamable HTTP on port 3000. When stdin is not a terminal, it speaks MCP over stdio and still opens the HTTP port. Logs during stdio mode go to stderr so they do not mix with the protocol.
Records are stored durably in a JSON file. The default path is ~/.milestone/milestone.json. Set MILESTONE_DATA_PATH to move it. One server process owns that file. Do not point it at another product's data file.
OAuth uses the same idea as a Supabase authorization server with dynamic client registration. Set these on the server process, not in an MCP header:
APP_BASE_URL(defaulthttp://localhost:3000)SUPABASE_URLSUPABASE_ANON_KEYSTRIPE_SECRET_KEYSTRIPE_WEBHOOK_SECRETSTRIPE_PRICE_MONTHLYandSTRIPE_PRICE_YEARLY(Stripe catalog ids, not a product price)OPENAI_APPS_CHALLENGE(plain-text token served at/.well-known/openai-apps-challenge; the path returns 404 when unset)
Tool calls other than discovery require a signed-in account whose subscription status is active or trialing.
More from Ouroboros: https://ouroborosapps.com
This server cannot be deployed
Maintenance
Related MCP Connectors
Freelance deposit and payment schedule for AI assistants
AI invoice follow-up emails for freelancers. Draft-only, never sends for you.
Freelance invoice line items, rates, due dates, and late terms for AI assistants
Month-end billing for consulting, architecture and engineering firms: your AI assistant previews each invoice from approved time, retainers and progress billing, then drafts them for your review. Also reports utilization, project profitability, WIP and cash flow.
Related MCP Servers
- AlicenseNot gradedqualityBmaintenanceDeposit by Ouroboros Apps (https://ouroborosapps.com). Freelance deposit and payment schedule: approved deposits, payment dates, and client wording; deposit waivers and date changes need approval. Connect by pasting https://deposit-continuity2.vercel.app/mcp into Claude, Cursor, Grok, or ChatGPT developer mode (OAuth). Docs: https://ouroborosapps.com/docs/deposit8 npmMIT
- AlicenseNot gradedqualityBmaintenanceScope by Ouroboros Apps (https://ouroborosapps.com). Freelance scope of work: approved scope, rates, deadlines, and change orders, so an assistant cannot promise work or discounts that were not approved. Connect by pasting https://scope-continuity2.vercel.app/mcp into Claude, Cursor, Grok, or ChatGPT developer mode (OAuth). Docs: https://ouroborosapps.com/docs/scope231 npmMIT
- AlicenseNot gradedqualityBmaintenanceClaim by Ouroboros Apps (https://ouroborosapps.com). Brand claims and marketing copy compliance: approved claims, offers, proof, brand voice, and banned phrases, with a check that rejects copy inventing a guarantee or discount. Connect by pasting https://claim-continuity2.vercel.app/mcp into Claude, Cursor, Grok, or ChatGPT developer mode (OAuth). Docs: https://ouroborosapps.com/docs/claim20 npmMIT
- AlicenseNot gradedqualityBmaintenanceInvoice by Ouroboros Apps (https://ouroborosapps.com). Freelance invoice records: approved invoice line items, quantities, agreed rates, due dates, and late terms; invoice changes need explicit approval. Connect by pasting https://invoice-continuity2.vercel.app/mcp into Claude, Cursor, Grok, or ChatGPT developer mode (OAuth). Docs: https://ouroborosapps.com/docs/invoice3 npmMIT