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PLAYBOOK - CREWAI

Automate your sales with CrewAI.

Wire LetSign into your CrewAI crew and a closer agent drafts the proposal, the pricing options and the contract as one of its tasks - then stages it for your review. Your client opens one link, picks a plan, signs and pays into your own Stripe.

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THE STACK

Five links in one chain.

Your crew does the thinking, LetSign does the contracting, Stripe does the collecting. You stay in the loop exactly once - at send time.

THE STACK CrewAIyour crew drafts LetSign MCPtools, not copy-paste Contract linkyou review, you send Client signspicks a plan, verifies Stripe payoutyour Stripe, not ours One crew run in, one signed and paid contract out.
SETUP

From crew definition to signed and paid, in five steps.

No webhooks, no custom API client. The whole setup is one adapter, one Stripe connection and one task description.

1

Point MCPServerAdapter at LetSign

CrewAI consumes remote MCP servers through MCPServerAdapter from the crewai-tools package. Configure it with the LetSign endpoint and the streamable-http transport, then pass the tools to your agents:

from crewai import Agent
from crewai_tools import MCPServerAdapter

letsign = {"url": "https://<your LetSign endpoint>/mcp",
           "transport": "streamable-http"}

with MCPServerAdapter(letsign) as tools:
    closer = Agent(role="Closer", tools=tools,
                   goal="Stage proposals for human review")

Get your endpoint from app.letsign.ai. LetSign is hosted, so the server is already publicly reachable.

2

Connect your Stripe inside LetSign

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.

3

Describe the closer's task

Give your closer agent a task description the way you would brief a colleague. One proven brief:

TASK DESCRIPTION

"Draft the retainer proposal for Meridian Consulting from the discovery notes: three tiers, the middle one at the number agreed on the call. Stage it in LetSign for human review and report the proposal link back. Do not send it."

4

Review, then send

Your closer 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.

5

Your client picks a plan, signs and pays

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 graphs over crews? The same stack runs in LangGraph. Want a local agent with a friendly CLI instead of a framework? There is a Goose playbook too. And for a no-code chat setup, start with Claude.

WHAT YOUR CREW CAN DO

Your crew, now closing.

AUTHOR PROPOSALS

Conditional pricing, built in

Your closer agent drafts the whole proposal with up to several plans your client can choose from - three tiers, optional add-ons, the works - straight from your discovery notes.

TRACK STATUS

Ask, and it knows

"Has Meridian signed yet?" A crew task can check proposal status through the MCP: opened, plan picked, signed, paid - without you opening a dashboard.

ADAPT TERMS

Renegotiate in one sentence

Client asks for net-60 or a 10% discount? Update the task, and your closer revises the terms and restages the proposal for your review.

COLLECT PAYMENT

Your Stripe, your money

One-off invoices, subscriptions, or save-card-on-file - collected through your own Stripe account at signature time, not weeks later.

And everything your crew 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 agents and you work on the same object, and neither is a second-class citizen.

FAQ

CrewAI questions, answered.

How does a CrewAI crew use the LetSign MCP?

Through MCPServerAdapter from the crewai-tools package. Point it at the LetSign remote MCP endpoint with the streamable-http transport and the adapter exposes LetSign's tools as ordinary CrewAI tools. Pass them to any agent in your crew, and that agent can draft proposals, check status and stage contracts as part of its tasks.

Do I need to write code?

A little Python, yes. CrewAI is a developer framework, so wiring up MCPServerAdapter and defining your agents and tasks happens in code, but it is a handful of lines, not an integration project. And everything the crew creates is also fully editable by hand in the LetSign app, no code required.

What does LetSign cost?

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.

Who sends the contract?

You do. Your crew 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.

READY WHEN YOUR CREW IS

Your next contract is one crew run away.

Add the adapter, connect Stripe, and let your crew stage the next proposal for your review.

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