The whole close runs in one ChatGPT conversation: paste the call, get a personalized proposal drafted through the LetSign connector, and send a link your client signs and pays on. One human review stands between the chat and the money.
ChatGPT holds the conversation, LetSign closes it, your own Stripe collects. Custom connectors require ChatGPT Developer Mode, available on Plus, Pro, Business and Enterprise.
No SDK, no webhooks, no integration project. The whole motion runs inside one ChatGPT conversation on two connections and one prompt.
You take the sales call the way you always do. Then open ChatGPT and paste the transcript or your summary: Fathom, Granola or Fireflies output works, and so do plain notes. Ask ChatGPT to summarize the scope, the numbers and the objections first, so you agree on what was actually said before anything gets drafted.
With the LetSign connector enabled in Developer Mode, ChatGPT authors the proposal in the same conversation: the scope in the client's own words, conditional pricing tiers your client can choose between, the terms you discussed. Connect Stripe once inside LetSign, then use one proven opener:
"Here is the transcript from this afternoon's call with Arden Labs. Summarize the scope and the numbers, then draft their onboarding proposal with the LetSign connector - three tiers, the middle one at the figure Priya quoted - and stage it for my review."
ChatGPT stages the proposal; nothing sends itself. You read every line, adjust a tier or a clause if you like, and press send. The human send-gate is a feature of the stack, not a limitation.
Your client opens one public link, chooses between the plans you offered, verifies their email and signs a binding e-signature. Remember: the sender never signs. The client does.
Payment is collected at signature time through your own Stripe account: one-off, subscription or save-card-on-file. LetSign never holds your funds.
This page is the in-chat recipe; the deep dives live one level down. Start with the ChatGPT playbook for the Developer Mode connector setup, zoom out to the full AI SDR stack, or read how to get paid from an AI agent.
The proposal is drafted from the transcript you pasted, so it opens with the client's own words, their numbers, their deadline. Not a template with a name swapped in.
Client wants net-60 or a smaller tier? Tell ChatGPT in one sentence; it updates the terms and restages the proposal for your review. No export, re-edit, re-send cycle.
The same link carries plan choice, email verification, binding signature and payment. There is no gap between yes and paid where the deal can cool.
The recipe holds no matter which brand fills each slot. Swap freely; the LetSign layer and your Stripe stay put.
| LAYER | IN THIS RECIPE | SWAP IT FOR |
|---|---|---|
| The agent | ChatGPT (Developer Mode) | Claude or Claude Code when you would rather run the same motion there |
| The notes | Pasted transcript | Fathom, Granola, Fireflies or any tool that turns the call into text you can paste |
| The automation rail | Plain conversation | Zapier (beta, via MCP Client by Zapier) or Make when you want trigger-driven runs instead of a chat window |
Yes. Custom MCP connectors like LetSign run through Developer Mode: open Settings -> Connectors -> Advanced -> enable Developer Mode, then choose Create connector and paste the LetSign MCP URL (streamable HTTP with OAuth). Developer Mode is available on ChatGPT Plus, Pro, Business and Enterprise, and the full LetSign toolset runs only there.
Into your own Stripe account, directly. LetSign never holds funds: when your client pays at signature time, whether one-off, subscription or save-card-on-file, the charge runs through the Stripe account you connected, and the payout follows your normal Stripe schedule.
The Free plan is $0 with a 0.20% fee on payments collected through it. The launch plan is $19 per month until October 1, 2026, and that price is locked until October 1, 2028; after launch the standard price is $49 per month. Paid plans pay 0% on payments up to $20,000 per month, then 0.05% above that.
No, and that is by design. ChatGPT stages the proposal through the LetSign connector; nothing sends itself. You review every line and press send yourself. Everything the connector does is also fully editable by hand in the LetSign app, so you can adjust a tier or a clause without touching the chat. And the sender never signs: your client does.
Install LetSign free, connect your Stripe, enable Developer Mode, and stage the next proposal without leaving the conversation.
INSTALL LETSIGN FREE