The Venture Codex

Participated · Seed · Aug 2026

Lemma builds production monitoring infrastructure for autonomous AI agents by capturing structured traces of agent executions, including LLM calls, tool usage, inputs and outputs, retrieval steps, timing data, and errors. Its platform analyzes those traces to identify recurring semantic failures, prioritize issues, and surface alerts. The company aims to detect silent failures where agents appear to succeed technically but produce incorrect outcomes. Lemma was founded by Jerry Zhang and Cole Gawin and participated in Y Combinator’s Fall 2025 cohort. It recently raised $2.3 million in a pre-seed round to accelerate development of its monitoring and failure-detection tools. Initially, Lemma plans to focus on supporting startups that are already running AI agents in production.

Participated · Equity · Sep 2025

Fiveonefour offers an open-source developer toolkit (the Moose Stack) plus a managed cloud platform (Boreal) and AI agents/tooling (Sloan) to simplify building analytical backends. The Moose Stack is a fast-growing TypeScript and Python toolkit that abstracts data infrastructure complexity so developers can integrate AI-ready analytics directly into applications. Installs of the Moose Stack have doubled month over month, and customers across healthcare, manufacturing, and connected fitness use the stack for user-facing analytics. F45 Training uses Fiveonefour to power its Lionheart biometric analytics feature; members who engage with Lionheart are 2.5X more valuable than average. Fiveonefour cites integrations with ClickHouse, Kafka, RedPanda, Temporal, and Redis and emphasizes developer- and agent-friendly APIs and MCPs. The company plans to accelerate AI agent development, expand enterprise support, deepen technical partnerships, and invest in its open-source community.

Participated · Equity · Jun 2025

Freeplay is a Boulder, CO-based provider of a platform for AI teams to build products and agents. It offers tools for prompt and model management, automated evaluations, and comprehensive LLM observability. The platform includes a customizable playground, batch testing, and integrated workflows for data labeling, dataset management, and production monitoring. It is designed for product managers, designers, domain experts, and developers to collaboratively build, test, and deploy AI-powered features. Teams from the Fortune 100 to leading startups already use the product. Freeplay recently raised $5.6M and plans to use the funds to grow its team, expand go-to-market efforts, and support its global community of AI builders. Freeplay offers a platform combining developer integrations and a web-based dashboard for building, experimenting with, and testing apps powered by text-generating large language models. The dashboard surfaces user interactions, estimated running costs, and average latency, while the platform lets teams swap models from different vendors and experiment with prompts. Freeplay includes tools for custom evaluations that leverage “auto-evaluators” (automated LLM-powered tests) alongside human labeling workflows to create feedback loops and datasets for optimization and fine-tuning. The company targets product development teams that are new to AI by providing beginner-friendly experimentation features and end-to-end workflows intended to move teams from prototype to production. Founders Ian Cairns and Eric Ryan, both ex-Twitter product and engineering leads, started the company last year after observing enterprise challenges adopting LLMs. Early customers are paying “several hundred” to “several thousands” of dollars per month, and Freeplay plans to grow its 10-person team to about 12–15 employees and bring the core product to market.

Participated · Equity · Mar 2025

Catio provides an AI-powered Copilot designed to simplify and optimize architecture decision-making by combining generative AI with architecture expertise. Led by CEO Boris Bogatin and CTO Toufic Boubez, the product delivers a continuously updated digital twin for 360° architecture visibility. It offers 24/7 AI-powered insights with interactive intelligence and instant Q&A for architecture decisions. The platform includes decision-intelligence tools that the company says can improve tech architectures by 80%. Catio intends to use recent funding to expand AI capabilities, scale product development, and grow customer adoption.