Connect
Optimize
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Live 75 Actions
Nutshell MCP Server
for AI Agents
StackOne's Nutshell MCP server gives AI agents 75 ready-to-use actions for Nutshell — with built-in authentication, security, governance, token efficiency, and high tool-calling accuracy.
Nutshell MCP Server
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StackOne
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75 Agent Actions
Create, read, update, and delete across Nutshell — and extend your agent's capabilities with custom actions.
Authentication
Agent Tool Authentication
Per-user OAuth in one call. Your Nutshell MCP server gets session-scoped tokens with zero credentials stored on your infra.
Agent Auth →
Security
Agent Protection
Every Nutshell tool response scanned for prompt injection in milliseconds — 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 Nutshell call.
Tools Discovery →What is the Nutshell MCP Server?
A Nutshell MCP server lets AI agents read and write Nutshell data through the Model Context Protocol — Anthropic's open standard for connecting LLMs to external tools. StackOne's Nutshell MCP server ships with 75 pre-built actions, fully extensible via the Connector Builder — plus managed authentication, prompt injection defense, and optimized agent context. 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 Nutshell MCP Tools and Actions
Every action from Nutshell's API, ready for your agent. Create, read, update, and delete — scoped to exactly what you need.
Users
- List Users
Retrieve a list of all users in the Nutshell account
- Get User
Retrieve a specific user by their ID
Contacts
- Create Contact
Create a new contact (person) in Nutshell
- List Contacts
Retrieve a paginated list of contacts in Nutshell
- Get Contact
Retrieve a specific contact by their ID
- Update Contact
Update an existing contact by ID using JSON Patch operations
- Delete Contact
Delete a contact from Nutshell
Contact Custom Fields
- Create Contact Custom Field
Create a new custom field definition for contacts
- Get Contact Custom Fields
Retrieve custom field values for a specific contact
Accounts
- Create Account
Create a new account (company) in Nutshell
- List Accounts
Retrieve a paginated list of accounts in Nutshell
- Get Account
Retrieve a specific account by its ID
- Update Account
Update an existing account by ID using JSON Patch operations
- Delete Account
Delete an account from Nutshell
Account Custom Fields
- Create Account Custom Field
Create a new custom field definition for accounts
- Get Account Custom Fields
Retrieve custom field values for a specific account
Leads
- Create Lead
Create a new lead (sales opportunity) in Nutshell
- List Leads
Retrieve a paginated list of leads in Nutshell
- Get Lead
Retrieve a specific lead by its ID
- Update Lead
Update an existing lead by ID using JSON Patch operations
- Delete Lead
Delete a lead from Nutshell
Lead Custom Fields
- Create Lead Custom Field
Create a new custom field definition for leads
- Get Lead Custom Fields
Retrieve custom field values for a specific lead
Outcomes
- List Outcomes
Retrieve a list of all lead outcomes in Nutshell
- Get Outcome
Retrieve a specific lead outcome by its ID
Activitys
- Create Activity
Create a new activity in Nutshell
- Get Activity
Retrieve a specific activity by its ID
- Update Activity
Update an existing activity by its ID
Tasks
- Create Task
Create a new task in Nutshell
- List Tasks
Retrieve a paginated list of tasks in Nutshell
- Get Task
Retrieve a specific task by its ID
- Update Task
Update an existing task by ID using JSON Patch operations
- Delete Task
Delete a task from Nutshell
Notes
- Create Note
Create a new note in Nutshell
- List Notes
Retrieve a paginated list of notes in Nutshell
- Get Note
Retrieve a specific note by its ID
- Delete Note
Delete a note from Nutshell
Tags
- Create Tag
Create a new tag in Nutshell
- List Tags
Retrieve a list of all tags in the Nutshell instance
- Delete Tag
Delete one or more tags from Nutshell
Sources
- Create Source
Create a new lead source in Nutshell
- List Sources
Retrieve a list of lead sources in Nutshell
- Delete Source
Delete a lead source from Nutshell
Products
- List Products
Retrieve a list of products in Nutshell
- Get Product
Retrieve a specific product by its ID
- Delete Product
Delete a product from Nutshell
Product Categorys
- Create Product Category
Create a new product category in Nutshell
- Get Product Category
Retrieve a specific product category by its ID
Other (27)
- List Contact Items
Retrieve all contacts in a list item format with additional filtering and sorting fields
- List Contact Fields
Retrieve the list of fields available for contacts
- List Contact Custom Field Attributes
Retrieve all contact custom field definitions in the Nutshell instance
- List Account Items
Retrieve all accounts in a list item format with additional filtering and sorting fields
- List Account Fields
Retrieve the list of fields available for accounts
- List Account Types
Retrieve all account types in the Nutshell instance
- List Industries
Retrieve the list of valid industries in Nutshell
- List Account Custom Field Attributes
Retrieve all account custom field definitions in the Nutshell instance
- List Lead Items
Retrieve all leads in a list item format with additional filtering and sorting fields
- Get Lead Stages
Retrieve the stage progression data for a specific lead
- Get Leads Report
Generate a report for leads with customizable filtering and grouping
- List Lead Fields
Retrieve the list of fields available for leads
- List Lead Custom Field Attributes
Retrieve all lead custom field definitions in the Nutshell instance
- List Activities
Retrieve a list of activities in Nutshell
- List Activity Types
Retrieve all available activity types in Nutshell
- List Product Categories
Retrieve all product categories in Nutshell
- Update Lead Status
Update the status of a lead including outcome, competitors, and products
- Set Lead Pipeline
Assign a lead to a pipeline (stageset)
- Undelete Contact
Restore a previously deleted contact by their ID
- Undelete Account
Restore a previously deleted account by its ID
- Undelete Lead
Restore a previously deleted lead by its ID
- Reopen Lead
Reopen a previously closed lead
- Watch Lead
Toggle notifications for a lead
- Undelete Note
Restore a previously deleted note by its ID
- Undelete Tag
Restore a previously deleted tag by its ID
- Undelete Source
Restore a previously deleted lead source by its ID
- Undelete Product
Restore a previously deleted product by its ID
Nutshell AI Agent Use Cases
Connect your AI agent to Nutshell and help your team scale the sales operations they run by hand today.
Post-Demo Follow-Up
Use StackOne to connect your AI agent to your CRM, email, and calendar tools to automate post-demo follow-up.
View Deal Risk Scoring
Use StackOne to connect your AI agent to your CRM, email, and calendar tools to automate deal risk scoring and pipeline alerts.
View Outbound Prospecting
Use StackOne to connect your AI agent to your CRM, sales engagement, and messaging tools to automate outbound prospecting.
ViewSet Up Your Nutshell MCP Server in Minutes
One endpoint. Any framework. Your agent is talking to Nutshell in under 10 lines of code.
MCP Clients
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>"
]
}
}
}More CRM MCP Servers
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Nutshell MCP Server Resources
MCP Code Mode: Keeping Tool Responses Out of Agent Context
Anthropic's code_execution processes data already in context. Custom MCP code mode keeps raw tool responses in a sandbox. 14K tokens vs 500.
11 min
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
Nutshell MCP Server FAQ
Nutshell MCP server vs direct API integration — what's the difference?
A Nutshell MCP server and direct API integration serve different use cases. Direct API integration is for software-to-software — backend code calling Nutshell. A Nutshell MCP server is for AI agents — MCP clients like Claude and Cursor, plus framework agents built with OpenAI, LangChain, or Vercel AI — discovering and calling Nutshell at runtime. StackOne provides both.
How does Nutshell authentication work for AI agents?
Nutshell authentication for AI agents works through a StackOne Connect Session. Create one via the dashboard or the SDK — you get an auth link and ready-to-paste config for Claude Desktop, Cursor, and other MCP clients. Your user authenticates their own Nutshell account; StackOne handles token exchange, storage, and refresh. Credentials never reach the LLM, and each user is isolated via
origin_owner_id.Are Nutshell MCP tools vulnerable to prompt injection?
Yes — Nutshell MCP tools can be vulnerable to indirect prompt injection. Any tool that reads user-written content — documents, messages, tickets, records, or free-text fields — is a potential vector. StackOne Defender scans every tool response before it enters the agent's context — regex patterns in ~1ms, then a MiniLM classifier in ~4ms. 88.7% accuracy, CPU-only.
What is the context bloat of a Nutshell agent and how do I avoid it?
Context bloat happens when Nutshell tool schemas and API responses eat your Nutshell agent's memory, preventing it from reasoning effectively. A single Nutshell query can return a massive JSON response, and connecting multiple tools compounds the problem. Tools Discovery and Code Mode reduce context bloat — loading only relevant tools per query and keeping raw responses out of the agent's context.
Can I limit which actions my Nutshell agent can access?
Yes — you can limit which actions your Nutshell agent can access directly from the StackOne dashboard. Toggle actions on or off, or restrict them to specific accounts, with no code changes to your agent. Session tokens can be scoped to exact actions so if one leaks, exposure stays contained.
Can I create custom agent actions for my Nutshell MCP server?
Yes — you can create custom agent actions for your Nutshell MCP server using Connector Builder. It's an integration agent your coding assistant (Claude Code, Cursor, or Copilot) can invoke to research Nutshell's API, generate production-ready connector YAML, test against the live API, and validate before you ship.
When should I NOT use a Nutshell MCP server?
Skip a Nutshell MCP server if your integration is purely software-to-software — direct Nutshell API integration is simpler when no AI agent is involved. For deterministic, compliance-critical operations (financial transactions, regulatory reporting), direct API gives you predictable behavior without agent-driven decision-making. MCP shines when AI agents need to dynamically discover and call Nutshell actions at runtime.
What AI frameworks and AI clients does the StackOne Nutshell MCP server support?
The StackOne Nutshell MCP server supports both. MCP clients (paste-and-go apps): Claude Desktop, Claude Code, Cursor, VS Code, Goose. Agent frameworks (code SDKs you build with): OpenAI Agents SDK, Anthropic, Vercel AI, Google ADK, CrewAI, Pydantic AI, LangChain, LangGraph, Azure AI Foundry.
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.