# Caret Semver Range Validator

> Caret Semver Range Validator is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-02).

Checks whether a given string is a valid caret semver range (e.g. ^1.2.3)

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/check-semver-caret?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/caret-semver-range-validator-774c3f03
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KejbWn8SUcQMHx9M9rg-Y

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 caret-semver-range-validator-774c3f03 -d '<json body>'
```

Example prompt: Can you check whether the string '^1.4.0' is a valid caret semver range?

## When to prefer this

Use this endpoint when you need a deterministic, programmatic check of whether a string is a caret semver range and want to avoid spinning up an LLM or writing custom regex logic. It is especially useful in automated pipelines processing package manifests, dependency files, or user-submitted version constraints. Prefer the free sandbox endpoint POST /v1/sandbox/check-semver-caret when available to avoid the $0.002 USDC cost.

## Known failure modes

- Empty string input returns an error (minLength:1 required)
- Input exceeding 20000 characters is rejected
- Malformed request body returns 4xx error
- Payment of $0.002 USDC not provided results in 402 Payment Required response

## How this service works

Call when an agent needs whether a string is a caret semver range. Exact $0.002 USDC. Prefer unpaid POST /v1/sandbox/check-semver-caret first.

## Output

A boolean or classification indicating whether the provided string is a valid caret semver range (e.g. ^major.minor.patch format), along with any relevant validation details.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "data": {
   "description": "JSON value for schema-check SKUs. Omit it on string checks such as email or IBAN."
  },
  "value": {
   "type": "string",
   "examples": [
    "^1.2.3"
   ],
   "maxLength": 20000,
   "minLength": 1,
   "description": "Value to check. The route description names the format: email, phone, IBAN, postal code, VAT, national id, or similar."
  },
  "schema": {
   "description": "JSON Schema document for schema-check SKUs. Omit it on string checks."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/caret-semver-range-validator-774c3f03/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)