London-based startup Portia AI has raised £4.4 million to help developers move AI agents from experimental pilots into real-world production—without losing control. Led by General Catalyst, the funding round supports Portia’s mission to bring transparency, predictability, and authentication to AI-powered agents that operate in business-critical environments.
Founded by ex-Stripe and Google leaders Emma Burrows and Mounir Mouawad, Portia AI offers an open-source framework and cloud platform that puts human oversight at the heart of autonomous systems. With regulatory demands intensifying in sectors like finance and customer service, Portia’s timing couldn’t be better.
While AI agents are often praised for their autonomy and reasoning skills, many still fail to scale into production due to one major problem—lack of visibility and control. Teams don’t just want smart agents; they want ones they can monitor, pause, steer, and trust. That’s where Portia steps in.
Tackling the Trust Problem in AI Agents
Over the past year, tech insiders have dubbed 2025 “the year of the agent.” Yet many organisations still hesitate to roll out AI agents because they feel like unpredictable black boxes. This is especially true in industries like fintech, where every action must be auditable and every outcome explainable.
Portia AI solves this gap by giving developers the tools to build AI agents that are easy to audit, secure to integrate, and responsive to human input at every critical step. The platform allows agents to work autonomously but ensures key decisions are validated by humans—particularly those with compliance implications or financial impact.
Its solution includes just-in-time authentication, making sure AI agents only access external systems with the right permissions at the right time. This keeps security tight while maintaining seamless integration with widely-used tools like Slack, Google Workspace, Zendesk, and GitHub.
Portia’s “clarification” mechanism adds another layer of trust. If an agent hits a roadblock—whether due to missing data, ambiguous prompts, or sensitive actions—it stops and asks for structured human input before continuing. That makes Portia agents feel more like collaborative coworkers than uncontrolled bots.
From Stealth to Spotlight: Founders With a Fintech Edge
The founding duo behind Portia bring deep roots in fintech and enterprise tech. Emma Burrows, former CTO of Stripe UK, built engineering teams and e-commerce platforms for brands like Charlotte Tilbury. Mounir Mouawad led the launch of Google Pay across 30 countries and introduced banking-as-a-service at Stripe.
They met while working at Stripe’s London office, united by a belief that AI agents should be tools developers can control—not systems they fear. That philosophy shaped Portia’s design: a developer-first platform where every agent step can be planned, observed, and audited.
Their shared love for science fiction also inspired the company’s name. “Portia” comes from Children of Time, a novel by Adrian Tchaikovsky, where a spider protagonist leads a civilisation through innovation and cooperation—values the founders hope to instil in their technology.
A New Standard for Human-AI Collaboration
Portia AI stands out in the fast-growing agent ecosystem by focusing on three core pillars: predictability, control, and secure integration. Its open-source SDK allows developers to build production-ready AI agents that can:
- Generate clear, step-by-step plans for each task
- Interact with APIs securely using time-bound tokens
- Pause for human input when handling complex or risky decisions
- Store, retrieve, and audit every agent plan and execution state
By allowing developers to extend and customise agent behaviours, Portia enables tailored solutions for a range of use cases—from fintech co-pilots and support automation to internal productivity bots.
With this new funding, Portia plans to expand its engineering team and roll out even more tools that make agents easier to build, manage, and trust in production settings. General Catalyst’s Juliet Bailin praised the founders’ vision, calling them “brilliantly positioned to build a generational company.”
As companies look to blend AI automation with human judgment, Portia AI is quickly becoming the go-to platform for building agents that work like trusted team members—not digital strangers.
