Actx0

Actx0 is a managed memory infrastructure service for AI agents and applications, designed to give agents persistent, searchable memory across sessions. It handles the full memory lifecycle — storing user messages, extracting short facts from them, and returning relevant hits before a model generates its next reply — all with sub-10ms P99 retrieval latency according to the product page.

What It Is

Actx0 sits between your application and your language model, acting as a dedicated memory layer rather than a general-purpose vector store. Developers POST user messages into an agent session; Actx0 indexes them, runs background extraction to distill useful content into compact facts (skipping low-signal turns like greetings), deduplicates and consolidates those facts within the session, and exposes a semantic search API so the right context can be injected into the prompt before each reply. The product page claims this approach can reduce token usage by up to 90% compared to replaying full transcripts.

How the Two-Call Model Works

The core workflow wraps around the model without replacing it:

• Add — POST user messages into a named agent session; Actx0 stores and indexes the turn.
• Learn — Background extraction converts useful message content into short, searchable facts and consolidates them within the session.
• Retrieve — Before generating a reply, search memories (and optionally workspace knowledge documents) and inject the hits into the prompt.

This keeps the developer in control of the model while Actx0 handles the memory plumbing.

Developer Experience and SDK Support

Actx0 ships official clients for Python (pctx0), Node.js, Go, and a REST API, so teams can integrate without operating their own vector store or search infrastructure. The homepage code sample shows creating an agent, opening a session, posting messages, and running a semantic memory search in under 20 lines of Python. Documentation is available at docs.actx0.com.

Target Use Cases

The product page highlights six verticals where persistent agent memory adds clear value:

• Customer Support — pick up ticket context without replaying the full thread
• Sales & CRM — store objections and commitments on a deal session
• Healthcare — remember appointment preferences across intake sessions
• Education — adaptive tutors that recall what worked in prior sessions
• DevTools — coding agents that remember project conventions
• E-Commerce — personal shopper agents with size, style, and purchase history

Enterprise and Multi-Tenant Architecture

For teams operating at scale, Actx0 provides workspaces, role-based access keys, audit logs, and per-team usage tracking. Memory namespaces are isolated per workspace while sharing managed infrastructure, removing the need to provision, patch, or scale vector store servers. The product is fully cloud-hosted with monthly self-serve billing and a separate Enterprise tier for custom limits and dedicated support.