gstinapi-mcp

An MCP server for gstinapi.in — GSTIN verification, GST return/compliance history, HSN/SAC code lookup, and India's MCA company registry, callable directly from Claude and other MCP clients.

This is a thin wrapper around the REST API at gstinapi.in/docs. It holds no logic of its own — every tool call is one authenticated HTTP request, and the response is returned as-is.

Setup

Get a free API key — 100 lookups on signup, no card required: https://www.gstinapi.in/register
Add this server to your MCP client config, e.g. for Claude Desktop / Claude Code (claude_desktop_config.json or .mcp.json):

config.json

{
  "mcpServers": {
    "gstinapi": {
      "command": "npx",
      "args": ["-y", "gstinapi-mcp"],
      "env": {
        "GSTINAPI_API_KEY": "your-api-key-here"
      }
    }
  }
}

No install step — npx fetches it on first use.

Tools

Tool	What it does
`verify_gstin`	Live registration lookup: legal name, status, taxpayer type, address
`get_gstin_returns`	GSTR-1/3B filing history for a financial year
`get_gstin_compliance`	Filing history summarised — counts, lag, last period
`get_gstin_filing_preference`	Monthly vs quarterly (QRMP), quarter by quarter
`resolve_gstin_to_company`	Probable MCA company match for a GSTIN (not authoritative — see caveat below)
`lookup_hsn_code`	Official description for an HSN/SAC code
`search_hsn_codes`	Find HSN/SAC codes from a description
`lookup_mca_company`	Company master data by CIN
`search_mca_companies`	Fuzzy company name search
`get_usage_stats`	Today's call count for the key (free)

Full field-level reference: https://www.gstinapi.in/docs

Accuracy notes

Every GSTIN lookup queries the GST network live — nothing is cached.
resolve_gstin_to_company is a probabilistic match, not an official mapping — no government dataset links a GSTIN to a CIN. Treat it as a scored guess (high/medium/low confidence), never as a confirmed fact.
No GST rate is returned from the HSN endpoints — a rate depends on more than the code alone, and the government's own master publishes no rate column.

Billing

Pay-per-use credits on your gstinapi.in account, no separate charge for this MCP server. Pricing: https://www.gstinapi.in/pricing

License

MIT