# Arch Tools — Session Create

> Arch Tools — Session Create is a paid API for AI agents from archtools.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Creates a new AI chat session with configurable TTL, model, and system prompt, returning a session identifier for subsequent interactions

## Facts

- Endpoint: POST https://archtools.dev/v1/tools/session-create
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/arch-tools-session-create-eb0c462f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_W7mnZiVYq5JTFAea3KPVZ

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability arch-tools-session-create-eb0c462f -d '<json body>'
```

Example prompt: Create a new AI session using claude with a 30-minute TTL and set the system prompt to 'You are a helpful customer support agent who only discusses billing issues.'

## When to prefer this

Use this endpoint when you need to establish a stateful AI session with a configurable model and system prompt before sending a series of messages. Prefer this over direct one-shot AI calls when your workflow requires persistent context, multi-turn conversations, or when you need to scope the AI to a specific persona or role via a system prompt. Especially useful as the first step in an agentic workflow where downstream tools will reference the same session.

## Known failure modes

- Invalid model name provided — returns 400 with model not supported error
- TTL value out of acceptable range — returns 400 with validation error
- Missing or malformed system prompt — returns 400
- Payment failure or insufficient USDC balance — returns 402
- Session creation quota exceeded — returns 429 rate limit error
- Internal server error during session initialization — returns 500

## How this service works

Arch Tools — session-create

## Output

Returns a JSON object containing the new session identifier and session configuration details (model, TTL, system prompt), which can be used to send messages or manage the session in subsequent API calls.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "model": {
   "enum": [
    "claude-sonnet-4-6",
    "claude-opus-4-6",
    "claude-haiku-4-5-20251001",
    "gpt-4o",
    "gpt-4o-mini"
   ],
   "type": "string",
   "default": "claude-sonnet-4-6",
   "description": "AI model to use"
  },
  "system": {
   "type": "string",
   "description": "Legacy alias for system_prompt"
  },
  "namespace": {
   "type": "string",
   "description": "Session namespace or grouping key"
  },
  "system_prompt": {
   "type": "string",
   "description": "System prompt for the session"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/arch-tools-session-create-eb0c462f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from archtools.dev](https://www.zero.xyz/host/archtools.dev/llms.txt)