SignNow MCP Server
for AI Agents
Connect your AI agent to StackOne's SignNow MCP server and give it 29 MCP tools out of the box. Auth, tool execution, and security all managed.
StackOne 
Coverage
29 Agent Actions
Agents can read, write, delete and run operations in SignNow. Extend your agent's capabilities with custom actions.
Authentication
Agent Tool Authentication
Per-user OAuth in one call. Your SignNow MCP server gets session-scoped tokens with zero credentials stored on your infra.
Agent Auth →
Security
Agent Protection
Every SignNow tool response scanned for prompt injection in milliseconds, with 88.7% accuracy, all running on CPU.
Prompt Injection Defense →
Performance
Max Agent Context. Min Cost.
Free up to 96% of your agent's context window to enhance reasoning and reduce cost, on every SignNow call.
Tools Discovery →What is the SignNow MCP Server?
A SignNow MCP server lets AI agents read and write SignNow data through the Model Context Protocol, Anthropic's open standard for connecting LLMs to external tools. StackOne's SignNow MCP server ships with 29 pre-built actions, fully extensible via the Connector Builder, plus managed authentication, prompt injection defense, observability, and agent execution runtime. Connect it from MCP clients like Claude Desktop, Claude Code, Cursor, Goose, and VS Code, or from agent frameworks like OpenAI Agents SDK, LangChain, and Vercel AI SDK.
All SignNow MCP Tools
Every StackOne action for SignNow, ready for your agent. Read, write, delete and run operations, scoped to exactly what you need.
Documents
- Upload Document
Upload a new document file to SignNow.
- Get Document
Retrieve a document's full details by id.
- Download Document
Download a document as a PDF or ZIP file.
- Delete Document
Permanently delete a document.
Merge Documents
- Merge Documents
Merge multiple documents into a single document.
Document Historys
- Get Document History
Retrieve the full audit history of a document.
Invite To Signs
- Invite To Sign
Send a document that already has signature fields out for signature, approval or viewing.
Cancel Invites
- Cancel Invite
Cancel the pending signing invite on a document that has not yet completed.
Document Groups
- Create Document Group
Group multiple documents together for a single signing flow.
- Get Document Group
Retrieve a document group's details by id.
- List Document Groups
List the caller's document groups with pagination.
- Delete Document Group
Remove a document group while keeping its documents intact.
Invite To Sign Document Groups
- Invite To Sign Document Group
Send a document group out for signature as one coordinated, multi-step flow.
Event Subscriptions
- Create Event Subscription
Create a webhook event subscription that calls a callback URL when an event fires.
- List Event Subscriptions
List configured webhook event subscriptions.
- Update Event Subscription
Update the event, entity and delivery config of an existing webhook subscription.
- Delete Event Subscription
Delete a webhook event subscription so its callback stops receiving events.
Folders
- Create Folder
Create a new folder for organizing documents under an existing parent.
- List Folders
List the caller's top-level system folders and their ids.
- Get Folder
Retrieve a specific folder's contents (documents, templates, groups) by id.
- Delete Folder
Permanently remove a folder from the caller's account.
Templates
- Create Template
Convert an existing document into a reusable template.
- List Templates
List templates stored in a folder.
- Get Template
Retrieve a template's full details by id.
Document From Templates
- Create Document From Template
Create a new document by copying a template.
Duplicate Templates
- Duplicate Template
Duplicate a template as a new, independent template.
Template Routing Details
- Get Template Routing Details
Retrieve a template's signer and approver routing configuration.
Users
- Create User
Create a new SignNow user account (requires an elevated organization-management token).
User Infos
- Get User Info
Retrieve the authenticated user's profile, subscription and organization details.
Set Up Your SignNow MCP Server in Minutes
One endpoint. Any framework. Your agent is talking to SignNow in under 10 lines of code.
Agent Frameworks
JSON{
"mcpServers": {
"stackone": {
"command": "npx",
"args": [
"-y",
"mcp-remote@latest",
"https://api.stackone.com/mcp?x-account-id=<account_id>",
"--header",
"Authorization: Basic <YOUR_BASE64_TOKEN>"
]
}
}
}Platform Resources
Comparing BM25, TF-IDF, and Hybrid Search for MCP Tool Discovery
Benchmarking BM25, TF-IDF, and hybrid search for MCP tool discovery across 916 tools. The 80/20 TF-IDF/BM25 hybrid hits 21% Top-1 accuracy in under 1ms.
10 min
Indirect Prompt Injection Defense for MCP Tools: A Technical Guide
MCP tools that read emails, CRM records, and tickets are indirect prompt injection vectors. Here's how we built a two-tier defense that scans tool results in ~11ms.
12 min
MCP vs A2A: Architecture, Security, and When to Use Each
MCP vs A2A: what each protocol standardizes, how they differ, their shared security risks including indirect prompt injection, and when to use one, both, or a hybrid architecture.
12 min
MCP vs API: What Hundreds of Connector Builds Taught Us
MCP wraps APIs, it doesn't replace them. After building hundreds of connectors that serve both, here's when each approach wins.
14 min read
SignNow MCP Server FAQ
Does StackOne have a SignNow MCP server?
SignNow MCP server vs direct API integration: what's the difference?
How does SignNow authentication work for AI agents?
origin_owner_id.Are SignNow MCP tools vulnerable to prompt injection?
What is the context bloat of a SignNow agent and how do I avoid it?
Can I limit which actions my SignNow agent can access?
Can I create custom agent actions for my SignNow MCP server?
When should I NOT use a SignNow MCP server?
What AI frameworks and AI clients does the StackOne SignNow MCP server support?
Put your AI agents to work
All the tools you need to build and scale AI agent integrations, with best-in-class connectivity, execution, and security.