# einvoice-validators-mcp

**MCP server that lets AI agents validate legally mandated e-invoices before submission** — Malaysia MyInvois (LHDN), Dominican Republic e-CF (DGII), Nigeria NRS/FIRS, Bolivia SIAT, Costa Rica Hacienda v4.4.

Each tool runs a keyless, stateless pre-flight against the official rules of the country: XSD structure, business rules, code lists, totals math, control codes (Bolivia's CUF rebuilt digit by digit, Costa Rica's 50-digit clave decomposed) and digital signatures (XAdES / XAdES-EPES / XML-DSig verified against the embedded certificate). Documents are validated in-memory and discarded — nothing is filed with any tax authority.

## Tools

| Tool | Country / regime |
|---|---|
| `validate_malaysia_myinvois` | 🇲🇾 MyInvois (LHDN/IRBM) — UBL 2.1 XML & JSON |
| `validate_dominican_republic_ecf` | 🇩🇴 e-CF (DGII, Ley 32-23) — signed XML |
| `validate_nigeria_firs` | 🇳🇬 NRS/FIRS FIRSMBS — UBL 2.1 XML & JSON |
| `validate_bolivia_siat` | 🇧🇴 SFV/SIAT (SIN) — signed XML + CUF |
| `validate_costa_rica_v44` | 🇨🇷 Comprobantes v4.4 (Hacienda) — signed XML, 8 document types |

Every response is a JSON report: `valid`, `wellFormed`, `signatureValid`, `errorCount`, `warningCount` and rule-coded `findings` the agent can reason about.

## Setup

1. Get a RapidAPI key (free): subscribe to the API(s) you need — **every one has a free plan**:
   - [Malaysia MyInvois](https://rapidapi.com/schatwiti/api/malaysia-myinvois-e-invoice-validator)
   - [Dominican Republic e-CF](https://rapidapi.com/schatwiti/api/dominican-republic-e-cf-validator-dgii)
   - [Nigeria NRS/FIRS](https://rapidapi.com/schatwiti/api/nigeria-nrs-firs-e-invoice-validator)
   - [Bolivia SIAT](https://rapidapi.com/schatwiti/api/bolivia-siat-e-invoice-validator-sfv)
   - [Costa Rica v4.4](https://rapidapi.com/schatwiti/api/costa-rica-e-invoice-validator-v4-4-hacienda)
2. Add the server to your MCP client.

### Claude Desktop / Claude Code

```json
{
  "mcpServers": {
    "einvoice-validators": {
      "command": "npx",
      "args": ["-y", "einvoice-validators-mcp"],
      "env": { "RAPIDAPI_KEY": "your-rapidapi-key" }
    }
  }
}
```

### Any MCP client (stdio)

```bash
RAPIDAPI_KEY=your-rapidapi-key npx -y einvoice-validators-mcp
```

## Usage notes for agents

- Pass the invoice **as-is** in the `invoice` argument. Signed documents are byte-sensitive: do not pretty-print, re-encode or "fix" them before validating.
- A non-compliant invoice is a normal result (`"valid": false` with findings), not an error.
- `valid: true` is an **informative pre-flight** ("structurally ready to submit"), not an acceptance by the authority — trust chains, live registries and clearance remain with the tax authority's online services.

## Why not just generate validation code?

The commodity layer (XSD) you can generate. What you cannot reliably generate: the gated or prose-only rule sets, the exact signature canonicalization proven against genuinely signed documents, and the maintenance when regulators change the rules (Costa Rica's TRIBU-CR migration, LHDN SDK updates). These APIs are maintained validators with real-world proof — the [technical write-ups](https://dev.to/chatwiti) show real outputs, including tamper detection on genuinely signed documents.

## Links

- Overview & landing: [samirchatwiti.github.io/e-invoice-validators](https://samirchatwiti.github.io/e-invoice-validators/)
- Also available on [Zyla API Hub](https://zylalabs.com/api-marketplace/legal+%26+compliance/malaysia+myinvois+e-invoice+validator+api/13423)
- Author: [Samir Chatwiti](https://github.com/SamirChatwiti) — GovTech/LegalTech solution architect

## License

MIT (this MCP client). The validation services themselves are commercial APIs.