Integration
Connect Karbon to fastbill
When New work item fires in Karbon, your agent runs Add Payment for Invoice in fastbill. Describe the whole flow and it is built, tested on every scenario and kept running.
What the catalog holds today. Ask for anything missing and your agent reads the API documentation and adds it.
Build solutions, not workarounds.
What do you want Karbon and fastbill to do together?
Ask the assistant
Connect your AI client
Give your AI client this address.
https://mcp.apiant.aiOne connection does both: ask your client to act in an app once, or have it build an automation that keeps running. Any client that takes a remote MCP server. Nothing to install. Create your free account, then sign in once in your browser.
Set it up in your client
Claude Code
Run this in the directory you want to work in.
claude mcp add --transport http -s project apiant-ai https://mcp.apiant.aiStart Claude Code there, approve the server, and sign in in the browser page it opens.
Claude Code guide (opens in a new tab)Claude, web and desktop
Open Customize, then Connectors, then Add custom connector, and paste the address. On Team and Enterprise an owner adds it first.
Setup guide (opens in a new tab)Cursor
Add the address to your MCP configuration as a server URL. Cursor signs you in in your browser.
Setup guide (opens in a new tab)Zed
Open Settings, then AI, then MCP Servers, then Add Server, then Add Remote Server.
Setup guide (opens in a new tab)Codex and the ChatGPT desktop app
Open Settings, then MCP servers, then Add server, and choose Streamable HTTP. From the terminal, Codex takes the address with its own add command and then signs you in.
Setup guide (opens in a new tab)Any other MCP client
Paste the address where the client asks for a remote MCP server URL, and name the server apiant-ai where it lets you. APIANT's skills reach the client over the same connection.
Setup guide (opens in a new tab)Example flows
What Karbon can start in fastbill
When New work item in Karbon
then Add Payment for Invoice in fastbill
Starting points drawn from the triggers and actions in the catalog today. Describe the flow you need, at any depth, and your agent builds it and tests every scenario before it ships.
Everything your agent can do with Karbon and fastbill
Triggers and actions 1 trigger · 34 actions
- New work item
Triggers when a new work item is created in Karbon.
- Add client group
Creates a new client group in Karbon, optionally with members, owner, manager and client team.
- Add note
Creates a note in Karbon, optionally assigned to a user and linked to work items, contacts, organizations or client groups.
- Add work item
Creates a new work item for a client in Karbon.
- Create Organization Contact
Creates a new Organization contact in Karbon.
- Create Person Contact
Creates a new person Contact in Karbon and returns the created Contact record.
- Find an Organization Contact
Finds Organization contacts in Karbon matching a full name, email address, external key or contact type, and returns the matching organizations.
- Find a Person Contact
Finds person contacts in Karbon by email address, full name, phone number, contact type or external key, and returns the matches.
- Get work item
Returns the details of a single Karbon work item, including its client, dates, status, fee settings and role assignments.
- List invoices
Returns the invoices in your Karbon account, optionally filtered by invoice status and sorted.
- List timesheets
Returns a list of timesheets from your Karbon account, optionally filtered by date, user, work item or status, with their time entries if requested.
- List users
Returns the users in your Karbon account, optionally filtered by name or email address.
- List work items
Returns the work items in your Karbon account, optionally filtered and sorted.
- Update client group
Renames an existing Karbon client group by changing its full name.
- Update Organization Contact
Updates the name or privacy level of an existing Organization contact in Karbon.
- Update Person Contact
Updates the name details or privacy level of an existing Person Contact in Karbon.
- Update work item
Updates a Karbon work item's title, description, dates, assignee, work type, role assignments or status. Fields left blank are not changed.
- Add Payment for Invoice
Adds full payment for invoice
- Add Payment for Revenue
Adds full payment for revenue
- Create Customer
Creates a new customer in FastBill
- Create Invoice
Creates a new invoice
- Create Offer
Creates a new offer in FastBill
- Create Revenue
Creates a revenue entry
- Delete Customer
Delete a FastBill customer by ID.
- Delete Invoice
Delete a FastBill invoice by ID.
- Delete Offer
Delete a FastBill offer/estimate by ID.
- Finalize Invoice
Converts an invoice draft to a final invoice
- Get Customer
Fetch a single FastBill customer by ID.
- Get Invoice
Fetch a single FastBill invoice by ID.
- Get Offer
Fetch a single FastBill offer/estimate by ID.
- Search Customer
Search for a Customer
- Search Invoice
Find an invoice
- Send Invoice by Email
Send an invoice by email
- Update Customer
Update fields on an existing FastBill customer.
- Update Invoice
Update fields on an existing (draft) FastBill invoice.
No trigger or action matches that. Ask your agent to add it: it reads the API documentation and builds what you describe.
Each app on its own
Reviews
What our customers say
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Questions
Karbon and fastbill, answered
What can start an automation from Karbon?
Any of Karbon's 1 trigger in the catalog, including New work item. Describe the moment in plain language and your agent picks the right one.
What can your agent do in fastbill when something happens in Karbon?
Any of fastbill's 18 actions, including Create Customer, Create Invoice, Create Offer and Create Revenue. Your agent maps the data both ways and tests every scenario before it ships.
Can it also run from fastbill to Karbon?
fastbill has no triggers in the catalog today, so automations start in Karbon. If you need the other direction, ask: your agent reads fastbill's API documentation and adds it.
Do I have to build a connector for Karbon or fastbill?
No. Both are in the catalog with their triggers and actions. You describe the automation; your agent builds it, tests every scenario and keeps it running.
Can my AI client use Karbon and fastbill without building an automation?
Yes. With your AI client connected to APIANT, ask it to do something in either app once and it runs that action on the spot. Ask for an automation and your agent builds it, tests every scenario and keeps it running. One connection covers both.
What happens when something fails?
Your agent works that out for you. It plans the failure paths along with the happy path, then tests every scenario before it ships.
Is there a free plan?
Yes. Every plan includes the agent, including free, and building from your own AI client spends no assistant credits.