Every system wanted its own kind of access
Modern Treasury runs payment operations for its customers. Internally, it set out to be AI-native. But most AI work still came down to pasting a question into a chat window and copying the answer back by hand, with nothing connected to the systems people actually used.
Moving to MCPs surfaced the real problem. Ankit mapped every downstream system against the people who needed it, and each connection wanted something different: OAuth here, an API key there, a shared credential somewhere else, with no clean way to track who was actually making a request. Every new MCP added another quirk for the IT team to carry.
“When I drew that matrix out, it was obvious we needed a gateway layer between the systems, the individuals, and the roles they actually had.”
Ankit Kumar
Engineering Leader, Modern Treasury
Doing that per-MCP for every user and agent would have been a constant point of friction, and a support burden the team didn't want. Modern Treasury needed one governed layer in front of everything.
What Modern Treasury deployed
Modern Treasury put Mint between its people and its systems. Engineering, customer support, sales, and marketing each get their own bundle with exactly the access they need. Open-source MCPs land the same way: the team vets a server, drops it in a bundle, and it's live, even with new requests coming in almost every other day.
On top of that access, the team used Mint's coworker agents to build a bank-operations agent. It checks the systems that hold the real answers, Notion for what's documented, the codebase and production data for what's actually shipped, error tracking for what just broke, and escalates to a person rather than guessing when they don't line up. Nothing is filed until a human reviews it.
Modern Treasury wrote up how they built it on their engineering journal.
“Your agent is only as good as the data and the governed access it has downstream. Get that right, and put rules in place to catch things like prompt injection and SQL injection.”
A bank-integration question used to take thirty minutes in the best case and four hours in the worst, often pulling an engineer into the codebase, for a six-to-eight-hour lag before a customer heard back. Now a first-draft answer takes a few minutes, and when an engineer does step in, the case arrives already scoped, with the relevant errors, code, and past incidents pulled.
“It saves our Technical Account Managers 30 minutes to 4 hours per case.”
Three agents are live now, with more on the way. Because the gateway sits under so much of what every team does, when a Claude release changes something, engineering and IT know within minutes.
What Modern Treasury told us
- RolloutWhat do you do at Modern Treasury?
- “I lead engineering on the application platform and infrastructure side, and I've been tasked with making sure Modern Treasury is AI-native. Everything we do internally runs on AI to streamline our workflows.”
- SecurityWhat pushed you toward an MCP gateway?
- “The appetite for AI was massive, but most of our work was putting a question into Claude or ChatGPT, getting a response, and copy-pasting information around. Once we moved to MCPs, it was clear that having every user and agent connect directly to all these downstream systems would be a massive point of friction, and supporting it would be really taxing on our IT team.”
- SecurityWas there a specific moment it clicked?
- “I started with a list of all our downstream systems and which people needed access to which. When I drew that matrix out, it was obvious we needed a gateway layer sitting between the systems, the individuals, and the roles they actually had.”
- SecurityHow were you handling access before?
- “It was MCP by MCP. We'd get a request, then go figure out how that MCP authenticated: does it do OAuth, does it need API keys, do we provision a shared credential and somehow track who's making the downstream requests. Every MCP had its own quirk, and that was very taxing for the IT team.”
- RolloutHow did you find Mint?
- “We were knee-deep in POCs with a couple of other gateway companies, and I was on Reddit and saw a comment mentioning Mint MCP. I started exploring, and it fit our needs exactly. What sold me on the call was the ability to build agents. It was alpha or beta at the time, but that was exactly the vision I had for enabling agents at Modern Treasury.”
- ImpactWhat's the main agent you've built?
- “A bring-your-own-bank agent. We codified our source code, past customer interactions, and knowledge from our support team into documents and rules, then gave it governed access to our downstream systems, our analytics database, and our error tracking. It answers most bank-integration questions on its own and knows when to escalate to the right person instead of guessing. The agent does the research; the human makes the call.”
- ImpactHow much time does that save?
- “In the best case we used to spend about thirty minutes on research; in the worst case, four hours and several people, including an engineer digging through the codebase. That was a six-to-eight-hour lag between a customer's question and our answer. Now it's a few minutes to a first draft, with an engineer in the loop only every now and then.”
- ImpactWho's on Mint now?
- “Engineering, customer support, sales, marketing, everyone uses it to reach the downstream systems. We create specific bundles for each group so they get exactly the access they need. There's been an explosion in the number of skills people build, just because of the access they now have to the tools underneath.”
- RolloutHow fast was it to stand up?
- “I had the first version of a bundle going in under a day. Going through all the MCPs and building the bundles took more planning than execution; the execution just worked, and the IT team has been really happy about that. The appetite never ends, though. Every other day someone asks to add an MCP, and being able to host open-source ones on Mint means we do our due diligence, assign it to a bundle, and it works out of the box.”
- ImpactHow do you think about build versus buy here?
- “I would never want to build this. For our core business it's undifferentiated heavy lifting, and Mint is really good at it. We tried a small build internally, AI-assisted, and there were just too many unknowns. It wasn't worth building and then maintaining it as the MCP space keeps changing this fast.”
Move from copy-paste from a chat window to an agent that answers
See how Mint gives agents governed access to the systems behind your product. Read more stories