Dunn
Work out invoice due dates, late fees and polite payment reminders so you get paid on time.
Free invoice tools. Calculates due dates from payment terms like net 30 or 2/10 net 30, works out late fees and how many days late an invoice is, and writes payment reminder emails that get firmer as a bill ages. No account or sign-in needed.
Try asking Muse: "Figure out when the invoice I sent on March 3 with net 30 terms is due, and draft a reminder if it's late."
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Source: Found in the official MCP Registry (org.getdunn/dunn) · First listed November 3, 2026
Last 24 hours
Each bar is one check, every 15 minutes. Green means it answered. Last checked 1 h ago.
Is it safe to connect?
What Muse can see: It does not ask you to sign in, so it cannot see your accounts. It only sees what Muse sends it from your request.
Before it acts: Read what Muse plans to do before you approve it, and remove the app from Muse when you stop using it.
musedirectory.ai is not part of Meta. More about how Muse handles your information
How to add it to Muse
Not in Muse's Connectors list yet, but Muse can still use it. Copy the request below and paste it into Muse. Muse asks before it shares anything with the app's site. Meta does not review apps used this way, so only use ones you trust. We tested this in the Muse app on September 24, 2026: Muse used an app's link directly this way and returned a live answer.
https://getdunn.org/mcpNot in Muse's Connectors list yet. Muse can still use it: its page gives you a request to paste into Muse.
Also use it in ChatGPT or Claude
Dunn is a remote MCP server, so any assistant that can add a custom connector by link can use it. Same link, same tools.
Add it to ChatGPT
- 1
Open ChatGPT settings
In ChatGPT, open Settings, then Connectors (called Apps & Connectors on some accounts).
- 2
Turn on developer mode
Under Advanced settings, switch on Developer mode. That is what lets you add a connector by link.
- 3
Create the connector
Choose Create, give it a name, paste the link as the MCP server URL, and save. If it needs a sign-in, ChatGPT asks for it here.
- 4
Use it in a chat
Start a chat, open the tools menu, pick the connector, and ask. ChatGPT asks before it runs a tool the first time.
Custom connectors need a paid ChatGPT plan, and on Team, Enterprise and Edu accounts only an admin can add them. Our "Working" label means the server answered us; it cannot tell whether your plan lets you add it. All connectors that work in ChatGPT
Add it to Claude
- 1
Open Claude settings
In Claude, open Settings, then Connectors.
- 2
Add a custom connector
Choose Add custom connector, give it a name, and paste the link.
- 3
Connect and use it
If it needs a sign-in, Claude sends you to it. Then turn the connector on in a chat from the tools menu and ask.
Custom connectors are available on paid Claude plans; on Team and Enterprise accounts an admin may need to add them. Our "Working" label means the server answered us; it cannot tell whether your plan lets you add it. All connectors that work in Claude
https://getdunn.org/mcpWhat people ask Muse to do
Technical details: safety screening, tools, response time and recent checks
Response time at the last check: 272ms. Worked in n/a of checks over 30 days.
Screening · November 3, 2026
Screened, no issues found
Screening looks for known threats and hidden instructions at the time of the check, and runs again weekly and whenever the tool list changes. It cannot see the server's code, so only connect what you need and review what Muse asks to do. How screening works.
Tools · 4
invoice_due_dateExact due date for an invoice from its date and payment terms ("net 30", "due on receipt", "EOM", "net 30 EOM", "2/10 net 30"), including any early-payment discount date.late_fee_calculatorWorks out a late fee: the amount, the new total, the exact day it applies, a ready-to-use line for the invoice, and whether the fee is in the usual range.how_late_is_this_invoiceHow many days late an invoice is (or until it is due), and what to send the client now and next, following a proven reminder schedule.payment_reminder_emailWrites the right payment reminder for where the invoice is now (before due, due today, late, or a final notice), with subject line. Polite by default; firm on request.Link
https://getdunn.org/mcpQuestions about Dunn in Muse
How do I connect Dunn to Muse?
Not in Muse's Connectors list yet, but Muse can still use it. Paste this into Muse: "Use Dunn to help me. It is a free service with an MCP server at https://getdunn.org/mcp. It does not need an API key. Ask me before you share anything with it." Muse asks before it shares anything with the app's site. Meta does not review apps used this way, so only use ones you trust. We tested this in the Muse app on September 24, 2026: Muse used an app's link directly this way and returned a live answer.
Is Dunn working right now?
At the last check (November 3, 2026, 04:31 UTC) the endpoint was working, answering in 272ms. It is checked every 15 minutes.
Is Dunn safe to connect to Muse?
It was screened on November 3, 2026 with the result "screened, no issues found". Screening checks the domain against threat feeds and reads the tools for hidden instructions and requests for passwords or card numbers. It cannot see the server's code, so grant only the access you need.
What can Dunn do in Muse?
It exposes 4 tools, including invoice_due_date, late_fee_calculator, how_late_is_this_invoice, payment_reminder_email. For example, you could ask Muse: "Figure out when the invoice I sent on March 3 with net 30 terms is due, and draft a reminder if it's late."
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This listing was added from public sources (Found in the official MCP Registry (org.getdunn/dunn)). If you build Dunn, claim it to correct the details and get your badge.
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