AI companion, chat & agent apps

The backend for AI companion apps.

An AI companion or chat app needs per-user conversation and memory storage, an LLM gateway with cost controls, subscriptions, safety moderation, and re-engagement push. Amba provides AI prompts (bring-your-own-key, per-call cost, spend budgets), typed collections with vector search for memory, entitlements, moderation, and push — the whole backend an agent installs over MCP.

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AI companion chatsAI tutors & coachescharacter/role-play apps

The same kind of agent that builds your app installs your backend — Amba provisions over hosted MCP, no browser signup required. AI companion apps are LLM front-ends with a memory problem and a billing problem: every conversation needs storing and recalling, every call costs money, and the product is usually subscription-funded. Amba’s AI gateway, vector collections, entitlements, and moderation cover exactly that. What is an agent-native backend?

what it needs

What a ai companion & chat app backend actually needs.

01
Conversation & memory storage
Per-user collections with vector search to store and semantically recall conversation memory.
02
LLM gateway with budgets
Versioned prompts across Anthropic/OpenAI/Mistral/Gemini, per-call cost, and per-prompt spend budgets.
03
Subscriptions
Entitlement-gated premium tiers — the usual AI-companion business model.
04
Safety & moderation
A moderation queue and policy for user-generated and model-adjacent content.
05
Re-engagement push
“Your companion misses you” nudges via scheduled and triggered push.
06
Auth
Anonymous-first identity so users can start instantly and link an account later.
how amba covers it

How does Amba handle memory and LLM costs?

AI prompts & gateway
Define versioned prompts, invoke them from any SDK with JSON output, streaming, and vision input; every response carries a per-call cost_usd and a per-prompt spend budget can deny calls once exhausted. Bring your own key — no markup.
Memory (vector search)
Typed collections with a vector column and findNearest for semantic recall of conversation memory, per-user isolated by default.
Entitlements
Gate premium tiers with user.entitled("pro"), readable from any tool, segment, or push trigger.
Moderation
A queue with keyword/regex rules and auto-approve-trusted for safety on user content.
Push & segments
Re-engagement push targeted by live segments (e.g. lapsed users).
questions

AI companion & chat apps backend — FAQ

What backend does an AI companion app need?

An AI companion app needs per-user conversation and memory storage, an LLM gateway with cost controls, subscriptions, safety moderation, and re-engagement push. Amba provides AI prompts with budgets, vector collections for memory, entitlements, moderation, and push as one backend.

Does Amba control LLM costs?

Yes. Every AI response carries a per-call cost_usd, and you can cap a prompt’s spend with a per-period USD budget that denies further calls once exhausted — plus a project-wide spend ceiling. You bring your own model key, so usage is on your bill with no markup.

Can Amba store and recall conversation memory?

Yes. Amba’s typed collections include vector columns and a findNearest query for semantic recall, per-user isolated by default — a built-in memory store with no separate vector vendor.

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