# 2s.io Dev Preflight — Command URL Validator

> 2s.io Dev Preflight — Command URL Validator is a paid API for AI agents from 2s.io, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-14).

Validates and preflights a shell command string by checking the target URLs it contains for reachability, TLS, DNS, HTTP method validity, and runnability.

## Facts

- Endpoint: POST https://2s.io/api/dev/preflight?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/2s-io-dev-preflight-command-url-validator-88dbbf96
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xhpksFmky_1RfHaZWJvYG

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 2s-io-dev-preflight-command-url-validator-88dbbf96 -d '<json body>'
```

Example prompt: Before I run this command, can you preflight it and tell me if the URL is actually reachable, TLS is valid, and it's safe to execute: curl -sSL https://api.github.com/users/octocat — also do a live HEAD probe.

## When to prefer this

Use this endpoint when an AI agent needs to validate a shell command (especially curl/wget) before executing it, confirm target URL reachability, or check for security red flags like private-network targeting or invalid TLS. Prefer over generic URL checkers because it parses the full shell command syntax and understands tool-specific semantics.

## Known failure modes

- Invalid or unparseable command string returns a non-runnable verdict with a reason field
- Target URL resolves to a private IP range — flagged as privateTarget: true
- DNS does not resolve — dnsResolves: false
- TLS certificate invalid — tlsValid: false
- HTTP probe returns non-2xx status when live probe is enabled
- Missing required 'command' field returns an error or empty items array

## How this service works

The (most) everything API: 575+ pay-per-call endpoints for AI agents — ground-truth data, a full AI gateway, and agent infrastructure (storage, queues, watchers). USDC via x402, no signup, no API keys, and upto billing: pay actual usage, not the quote.

## Output

Returns a structured JSON object with a verdict ('runnable' or otherwise), per-check boolean results (schemeOk, urlValid, hostPresent, methodValid, privateTarget, tlsValid, dnsResolves, reachable, httpStatus), the parsed target URLs, the detected tool, the mode (static/live), and a reason if not runnable. Also includes total count and source/provider metadata.

## Example request

```json
{
 "probe": true,
 "command": "curl -sSL https://api.github.com/users/octocat"
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "probe": {
   "type": "boolean",
   "description": "Also do a live guarded HEAD probe (default false)."
  },
  "command": {
   "type": "string",
   "description": "The shell command to check."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/2s-io-dev-preflight-command-url-validator-88dbbf96/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from 2s.io](https://www.zero.xyz/host/2s.io/llms.txt)