Connect LetSign to Goose and Block's open-source agent drafts the proposal, the pricing options and the contract from a single session - then stages it for your review. Your client opens one link, picks a plan, signs and pays into your own Stripe.
Goose does the thinking, LetSign does the contracting, Stripe does the collecting. You stay in the loop exactly once - at send time.
No SDK, no webhooks, no integration project. The whole setup is two connections and one prompt.
Grab your LetSign MCP endpoint URL from app.letsign.ai, then run goose configure in your terminal. Choose Add Extension, pick "Remote Extension (Streamable HTTP)" and enter the endpoint URI. Goose saves it as an extension available in every session.
Prefer a one-off run? Start a session with the extension attached directly: goose session --with-streamable-http-extension "<url>" with the LetSign MCP URL in place of <url>.
In the LetSign app, connect your own Stripe account once. From then on every payment - one-off, subscription, or save-card-on-file - is collected through your Stripe and lands in your account. LetSign never holds your money.
Talk to Goose the way you would brief a colleague. It runs on your machine, so it can read your local notes before it drafts. One proven opener:
"Read meridian-call-notes.md and draft the retainer proposal for Meridian Consulting - three tiers, the middle one at the number we discussed - then stage it for my review."
Goose stages the proposal; nothing sends itself. You read it, tweak anything you like (a discount, net-60 terms, a different tier), and press send. The human send-gate is a feature, not a limitation.
Your client opens one public link, chooses between the plans you offered (conditional pricing built in), verifies their email, signs a binding e-signature and pays through your Stripe - in a single sitting. Remember: the sender never signs. The client does.
Prefer another terminal agent? The same stack runs in Claude Code and the OpenAI Codex CLI. Building your own agent in code? There is a LangGraph playbook too.
Goose drafts the whole proposal with up to several plans your client can choose from - three tiers, optional add-ons, the works - straight from your call notes.
"Has Meridian signed yet?" Goose checks proposal status through the MCP: opened, plan picked, signed, paid - without you opening a dashboard.
Client asks for net-60 or a 10% discount? Tell Goose, and it updates the terms and restages the proposal for your review.
One-off invoices, subscriptions, or save-card-on-file - collected through your own Stripe account at signature time, not weeks later.
And everything Goose does here, you can also do by hand. Every proposal, template and setting is fully editable in the LetSign app - full parity with the MCP. That two-way door is the essence of an agent-native contract: your agent and you work on the same object, and neither is a second-class citizen.
Through its built-in extension system. Run goose configure in your terminal, choose Add Extension, then pick Remote Extension (Streamable HTTP) and enter the LetSign endpoint URI. For a one-off run you can instead start goose session --with-streamable-http-extension "<url>" with the LetSign MCP URL. Goose speaks MCP natively, so a hosted server like LetSign works out of the box.
No. goose configure is an interactive wizard, not a coding task: you pick Add Extension, choose Remote Extension (Streamable HTTP) and enter the endpoint URI. You connect Stripe once inside LetSign, then everything else happens in plain conversation with Goose. And if you ever prefer to work by hand, every proposal and template is fully editable in the LetSign app.
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.
You do. Goose drafts and stages the proposal, but nothing sends itself: a human reviews and presses send. And the sender never signs. Your client opens the link, picks a plan, verifies their email, signs a binding e-signature and pays through your Stripe.
Add the extension, connect Stripe, and let Goose stage the next proposal for your review.
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