assistant-ui
Open Source React.js Library for AI Chat
assistant-ui is a assistant-ui is a frontend library and optional cloud service for building AI chat interfaces and threaded agent experiences in React, TypeScript, and related runtimes. The pricing page shows a free tier and paid Cloud plans for hosted persistence and scaling. AI agent company selling to Developers building AI chat apps / agent interfaces, especially with TypeScript and React; assistant-cloud is for hosted conversation persistence/history/auth.. Latest disclosed round: Last known: Seed (2025) ($500,000, 2025-02-17). About 10 employees, +11.1% over 6 months.
Product
- Agent type
- assistant-ui is a frontend library and optional cloud service for building AI chat interfaces and threaded agent experiences in React, TypeScript, and related runtimes. The pricing page shows a free tier and paid Cloud plans for hosted persistence and scaling.
- Primary buyer
- Developers building AI chat apps / agent interfaces, especially with TypeScript and React; assistant-cloud is for hosted conversation persistence/history/auth.
- Integrations
- —
- MCP support
- —
- HQ
- San Francisco, California, US
- Founded
- 2024
- Profile ↗
Funding
- Date
- Feb 17, 2025
- Source
- Announcement ↗
- Investors
- Pioneer Fund; Y Combinator
Hiring
- Employees
- 10
- Growth 3m / 6m
- — / +11.1%
- Open roles (sample)
- —
- X mentions this week
- —
- X handle
- —
Top launch posts
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Recent news
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Sources
- Headcount
- Clay (LinkedIn)
- Open jobs
- —
- Traffic
- Clay (web traffic)
- X metrics
- —
- X handle (homepage-verified)
- —
- Clay enrichment
- Clay enrichment 2026-11-04
- seed_type
- YC directory
- funding_status
- Last known (aggregator source)
- funding_source_type
- aggregator
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About assistant-ui
What does assistant-ui do?+
Open Source React.js Library for AI Chat
How much has assistant-ui raised most recently?+
Last known: Seed (2025) of $500K on Feb 17, 2025, led by {"Y Combinator"}.
How many employees does assistant-ui have?+
About 10 (3-month growth —).
How is assistant-ui priced?+
Subscription, starting at $50/mo.
Cite this data
assistant-ui profile. Agent Market Map, The GTM Engineering Newsletter. Last verified Nov 4, 2026. https://agentmarketmaps.com/company/assistant-ui