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Connectors Fastbill
Live 57 Actions

Fastbill integration for AI agents

Connect your AI agent to 57 production-ready Fastbill actions via MCP, A2A, or SDK — with managed agent tool auth, optimized execution, and built-in security.

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Fastbill AI agent actions

57 production-ready actions for your agent to do more on Fastbill.

57 Actions
List Customers - Retrieve a list of customers from Fastbill with optional filtering.
Get Customer - Retrieve a specific customer by ID from Fastbill.
Create Customer - Create a new customer in Fastbill.
Update Customer - Update an existing customer in Fastbill.
Delete Customer - Delete a customer from Fastbill.
List Contacts - Retrieve contacts for customers from Fastbill.
Create Contact - Create a new contact for a customer in Fastbill.
Update Contact - Update an existing contact in Fastbill.
Delete Contact - Delete a contact from Fastbill.
List Invoices - Retrieve a list of invoices from Fastbill with optional filtering.
Get Invoice - Retrieve a specific invoice by ID from Fastbill.
Create Invoice - Create a new invoice draft in Fastbill.
Update Invoice - Update an existing invoice draft in Fastbill.
Delete Invoice - Delete an invoice draft from Fastbill.
Complete Invoice - Finalize an invoice draft and convert it to a completed invoice.
Cancel Invoice - Cancel a completed invoice in Fastbill.
Lock Invoice - Finalize an invoice in Fastbill.
Set Invoice Paid - Mark an invoice as paid in Fastbill.
Send Invoice By Email - Send a completed invoice to a recipient via email with PDF attachment.
Send Invoice By Post - Send a completed invoice via postal mail.
List Estimates - Retrieve a list of estimates/quotes from Fastbill with optional filtering.
Get Estimate - Retrieve a specific estimate by ID from Fastbill.
Create Estimate - Create a new estimate/quote in Fastbill.
Delete Estimate - Delete an estimate from Fastbill.
Send Estimate By Email - Send an estimate to a recipient via email with PDF attachment.
Convert Estimate To Invoice - Convert an existing estimate into an invoice.
List Recurring Invoices - Retrieve a list of recurring invoices from Fastbill.
Get Recurring Invoice - Retrieve a specific recurring invoice by ID from Fastbill.
Create Recurring Invoice - Create a new recurring invoice in Fastbill.
Update Recurring Invoice - Update an existing recurring invoice in Fastbill.
Delete Recurring Invoice - Delete a recurring invoice from Fastbill.
List Revenues - Retrieve a list of revenue entries from Fastbill with optional filtering.
Get Revenue - Retrieve a specific revenue entry by ID from Fastbill.
Create Revenue - Create a new revenue entry in Fastbill.
Set Revenue Paid - Mark a revenue entry as paid in Fastbill.
Delete Revenue - Delete a revenue entry from Fastbill.
List Expenses - Retrieve a list of expense entries from Fastbill with optional filtering.
Get Expense - Retrieve a specific expense entry by ID from Fastbill.
Create Expense - Create a new expense entry in Fastbill.
List Articles - Retrieve a list of products/articles from Fastbill.
Get Article - Retrieve a specific product/article by ID from Fastbill.
Create Article - Create a new product/article in Fastbill.
Update Article - Update an existing product/article in Fastbill.
Delete Article - Delete a product/article from Fastbill.
List Projects - Retrieve a list of projects from Fastbill with optional filtering.
Get Project - Retrieve a specific project by ID from Fastbill.
Create Project - Create a new project in Fastbill.
Update Project - Update an existing project in Fastbill.
Delete Project - Delete a project from Fastbill.
List Time Entries - Retrieve a list of time tracking entries from Fastbill with optional filtering.
Get Time Entry - Retrieve a specific time entry by ID from Fastbill.
Create Time Entry - Create a new time tracking entry in Fastbill.
Update Time Entry - Update an existing time entry in Fastbill.
Delete Time Entry - Delete a time entry from Fastbill.
List Templates - Retrieve a list of invoice/estimate templates from Fastbill.
List Documents - Retrieve a list of documents and folders from Fastbill.
Create Document - Create a document entry in the Fastbill inbox.

Do More, Build Less.

Integration Infrastructure for Fastbill AI Agents.

Multiple Interfaces

Access integrations via API, AI SDKs, MCP & A2A.

Fastbill MCP server
Managed Authentication

Pre-built authentication UI.

Agent auth
Falcon Engine

Every Fastbill action runs on Falcon.

Agent Execution Engine
StackOne Defender
StackOne Defender Meta PG v1 Meta PG v2 DeBERTa 88.7% 67.5% 63.1% 56.9% Detection accuracy

88.7% prompt injection detection.

Prompt injection defense

"What impressed us most about StackOne is its ambition and clarity. They're creating infrastructure that modern software and the entire AI agent ecosystem can rely on. The depth of secure integrations, the pace of delivery, and the team's foresight into AI's future uniquely position StackOne to redefine this category."

Luna Schmid, Partner at GV

"We've been impressed by how quickly and deeply StackOne integrates with complex enterprise systems -- and now, with their focus on agent-to-agent interoperability, they're unlocking even more powerful use cases for customers. StackOne delivers all of the above in a universal layer -- without compromise."

Barbry McGann, SVP at Workday Ventures

G2 - High Performer G2 - Easiest To Do Business With G2 - Users Love Us G2 - Users Most Likely To Recommend G2 - Easiest Admin

Product teams love building agent integrations with StackOne.

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