# AgentShelf RGB Color String Validator

> AgentShelf RGB Color String Validator is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.007/call, status unknown (last checked 2026-10-02).

Checks whether a given string is a valid CSS rgb() color value

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/check-color-rgb?utm_source=zero.xyz
- Price: $0.007/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentshelf-rgb-color-string-validator-0480fde4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_LalPSQo898tVwL9Pew806

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 agentshelf-rgb-color-string-validator-0480fde4 -d '<json body>'
```

Example prompt: Can you check whether the string 'rgb(255, 128, 0)' is a valid rgb() color value?

## When to prefer this

Use this endpoint when you need a fast, deterministic check of whether a string is a valid rgb() color — no LLM reasoning, no network lookups, just pure format validation. Prefer the free sandbox POST /v1/sandbox/check-color-rgb endpoint first to avoid the $0.007 USDC cost; use this paid endpoint when the sandbox is unavailable or when billing integration is required. Choose this over similar endpoints for hsl() or CSS named colors when you specifically need rgb() format validation.

## Known failure modes

- Empty or missing value field returns an error
- String exceeding 20,000 characters is rejected
- Malformed request body returns a 4xx error
- Service unavailable returns a 5xx error
- Payment not provided or insufficient USDC results in a 402 response

## How this service works

Call when an agent needs whether a string is an rgb() color. Exact $0.007 USDC. Prefer unpaid POST /v1/sandbox/check-color-rgb first.

## Output

Returns a boolean or structured result indicating whether the input string conforms to the rgb() CSS color format, with no data stored on the server.

## 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": [
    "rgb(255, 0, 170)"
   ],
   "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/agentshelf-rgb-color-string-validator-0480fde4/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)