Less than a month after abandoning the name Keywords AI for something more cryptic, the San Francisco startup now known as Respan has secured $5 million in seed funding. Gradient Ventures, Google's AI-focused investment arm, led the round that closed March 18, 2026.
The timing raises questions about whether the rebrand was a strategic prelude to the raise—or simply urgent. On February 20, 2026, the company announced it could no longer live with a name that evoked search engine optimization at a moment when its platform had evolved into something more ambitious: a system for monitoring, evaluating, and managing the sprawling infrastructure behind AI agents.
The new moniker, Respan, is a nod to distributed tracing—specifically the "span," a term engineers use to describe discrete units of work as data moves through complex systems. It's the kind of inside-baseball naming that signals a product built for developers, not marketers.
What They're Building
Respan calls what it does "proactive observability," which is less jargon than it sounds. The platform captures granular execution traces across AI agent workflows—every message exchanged, every tool invoked, every routing decision, every memory operation—and layers on continuous evaluation. The idea is to close the loop: don't just watch your AI systems run, but measure how well they're performing and act on what breaks.
One feature the company highlights is an "evaluation agent" that analyzes patterns in failed interactions and suggests fixes. There's also a gateway component that handles routing, caching, rate limiting, and fallback logic across what Respan claims is support for more than 500 models. Whether enterprises need access to quite that many models is another question, but the infrastructure bet is clear: flexibility over lock-in.
The scale hints at traction. As of mid-March, Respan says it processes over a billion logs monthly and routes 2 trillion tokens—serving more than 6.5 million end users across what it describes as "100-plus AI startups and enterprise teams." Customers include Retell AI, which builds voice agents; Mem0, a memory framework for AI systems; and the financial research platform AlphaSense.
The Founders and the Funding
Co-founders Andy Li and Raymond Huang both studied at the University of Illinois Urbana-Champaign. Li, now CEO, worked on AirPods product design at Apple before leaving without finishing his degree. Huang, the CTO, graduated with highest honors in three years and turned down robotics PhD offers to start the company instead. They founded Respan (then Keywords AI) in 2023 and went through Y Combinator's Winter 2024 batch.
The team has grown to 10, according to YC's directory. The fresh $5 million—backed by Y Combinator, Hat-Trick Capital, XIAOXIAO FUND, Antigravity Capital, Alpen Capital, and a handful of unnamed angels and AI founders—will fund hiring and infrastructure upgrades. The company hasn't disclosed valuation.
A Crowded, Consolidating Field
Respan isn't alone in chasing the observability opportunity. The space has gotten crowded fast as AI applications move from prototype to production. HoneyHive raised a total of $7.4 million—a $5.5 million seed round led by Insight Partners plus a $1.9 million pre-seed—announced in April 2025. LangChain's LangSmith came packaged with a $25 million Series A back in February 2024. Open-source alternatives like Langfuse, Portkey, Arize Phoenix, and Braintrust are all vying for developer mindshare.
Perhaps more telling: just two weeks before Respan's funding closed, Mintlify acquired Helicone—an open-source LLM gateway and observability tool—on March 3. That deal signaled consolidation may be starting, even as the category itself is still being defined.
Respan published a comparison guide the very next day, March 4, positioning its platform as the only one integrating observability, evaluation, and gateway functions into a single system. The framing was pointed, if not subtle.
For now, the company is betting that as AI agents grow more complex and more mission-critical, the demand for tools that can both watch and fix them in real time will justify the crowded field. Whether a billion monthly logs translates to a durable business remains the open question. But with Google's venture arm now on the cap table, Respan has at least bought itself time to find out.
