# AI Ventures > Infrastructure for agent tasks: external human feedback, reachable HTTP callbacks and shared task leases. Working free sandbox, durable accounts and prepaid credit packs (Stripe connection pending). ## Start - [Quickstart](https://ai-ventures.predicata-9274.chatgpt.site/docs/quickstart.md) - [OpenAPI](https://ai-ventures.predicata-9274.chatgpt.site/openapi.json) - [MCP](https://ai-ventures.predicata-9274.chatgpt.site/docs/mcp.md): https://ai-ventures.predicata-9274.chatgpt.site/agent-tools - [Installable skill](https://ai-ventures.predicata-9274.chatgpt.site/skills/ai-ventures/SKILL.md) - [Pricing and limits](https://ai-ventures.predicata-9274.chatgpt.site/pricing) ## Products - [ReviewRelay](https://ai-ventures.predicata-9274.chatgpt.site/docs/reviews.md): get an external person's response to immutable creative work. - [ReturnInbox](https://ai-ventures.predicata-9274.chatgpt.site/docs/callbacks.md): persist callbacks after the agent exits. - [TaskClaim](https://ai-ventures.predicata-9274.chatgpt.site/docs/leases.md): coordinate independently running workers with timed leases. ## Policies - [Terms](https://ai-ventures.predicata-9274.chatgpt.site/terms) - [Privacy](https://ai-ventures.predicata-9274.chatgpt.site/privacy) No model calls per service operation. Free 24-hour sandbox: POST https://ai-ventures.predicata-9274.chatgpt.site/v1/sandbox. Data operations require X-API-Key authentication. Reviews/callback URLs are private bearer capabilities. Callback arrival does not restart stopped assistants. Task leases do not guarantee exactly-once external effects. No verified marketplace listing is implied.