PKI Studio MCP

PKI Studio MCP is a local MCP server for AI-assisted PKI, ASN.1, DER, PEM, X.509 certificate, CSR, key, and PKCS#12 workflows. It exposes PKI Studio family libraries as MCP tools for AI assistants through stdio and Streamable HTTP transports.

Documentation: https://github.com/pkistudio/pkistudiomcp/wiki

Current version: 0.7.2

The server is designed for local assistant workflows first. Certificate parsing, ASN.1 parsing, key recognition, and PKCS#12 processing run inside the MCP server process. Network fetching is limited to the explicit fetch_certificate_network_resources tool.

Features

• stdio MCP server for local VS Code, GitHub Copilot, Claude Desktop, and other MCP clients.
• Streamable HTTP MCP server for local, containerized, or controlled remote deployments.
• ASN.1 / DER / BER / PEM parsing, summaries, node extraction, and decoded node values.
• OBJECT IDENTIFIER encoding, decoding, and name resolution through PkiStudioJS.
• X.509 certificate parsing through CertGadgets, including CDP/AIA/OCSP resource plans without automatic network access.
• PKCS#8 private key and SPKI public key recognition, key pair generation, key verification, certificate/key matching, CSR creation, and self-signed certificate creation through Private Key Gadgets.
• PKCS#12 / PFX import and export helpers for certificate and key bundles.
• ASN.1 Instance Builder tools for parsing supported ASN.1 definitions, validating schema/instance JSON, and building DER.
• ASN.1 Definition Sifter tools for ranking likely ASN.1 type definitions for DER/TLV data.
• MCP workflow prompts for certificate inspection, certificate/key comparison, and PKCS#12 analysis.
• Docker image for the Streamable HTTP server.

See the Wiki for details:

• Getting Started
• MCP Client Configuration
• Tool Guide
• Security Notes
• HTTP Deployment
• Testing
• Development

What Can I Ask?

• Parse this PEM certificate and summarize the issuer, subject, validity, extensions, and ASN.1 structure.
• Show all OIDs found in this DER data and resolve their names.
• Check whether this certificate matches this private key.
• Read this PKCS#12/PFX file and list contained certificates and keys.
• Generate a test key pair, CSR, or self-signed certificate.
• Identify likely ASN.1 type definitions for this DER data.
• Build DER from this ASN.1 definition and JSON instance.

For a longer prompt list, see Getting Started.

Tool Areas

• Certificate inspection: parse_certificate, parse_asn1, summarize_asn1, resolve_oid.
• DER / ASN.1 inspection: parse_asn1, summarize_asn1, describe_node, extract_asn1_node, asn1_node_value.
• OID utilities: encode_oid, decode_oid_value, resolve_oid.
• Key material: recognize_key_material, generate_key_pair, verify_key_pair, certificate_matches_key.
• CSR and test certificates: create_csr, create_self_signed_certificate.
• PKCS#12 / PFX: read_pkcs12, write_pkcs12.
• ASN.1 Definition Sifter: sift_asn1_definition_candidates, sift_pki_asn1_definition_candidates.
• ASN.1 Instance Builder: parse_asn1_definition, validate_asn1_schema, validate_asn1_instance, create_asn1_instance.

For all purpose-to-tool mappings, see the Tool Guide.

Install

Run the stdio MCP server from npm:

npx -y @pkistudio/pkistudiomcp

Run the Streamable HTTP MCP server from npm:

npx -y --package @pkistudio/pkistudiomcp pkistudiomcp-http

Package commands:

• pkistudiomcp: stdio MCP server.
• pkistudiomcp-http: Streamable HTTP MCP server.

MCP Client Quick Start

VS Code / GitHub Copilot .vscode/mcp.json:

{
  "servers": {
    "pkistudio": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@pkistudio/pkistudiomcp"]
    }
  }
}

Claude Desktop configuration:

{
  "mcpServers": {
    "pkistudio": {
      "command": "npx",
      "args": ["-y", "@pkistudio/pkistudiomcp"]
    }
  }
}

After configuring your client, try one of the prompts in What Can I Ask?. For client-specific details, see MCP Client Configuration.

Docker

Run the published Docker image:

docker run --rm -p 3000:3000 pkistudio/pkistudiomcp:latest

The Docker image starts the Streamable HTTP server by default. The MCP endpoint is http://127.0.0.1:3000/mcp, and health checks are available at http://127.0.0.1:3000/healthz and http://127.0.0.1:3000/readyz.

Pin a release version when reproducibility matters:

docker run --rm -p 3000:3000 pkistudio/pkistudiomcp:0.7.2

For HTTP deployment controls, see HTTP Deployment and Security Notes.

Development

Run local checks with:

npm install
npm run check
npm run test

Run the stdio server locally:

npm start

Run the HTTP server locally:

npm run start:http

For package or release-related changes, also run:

npm pack --dry-run

For standard checks, MCP smoke coverage, package preview, local Wiki clone conventions, and release workflow notes, see Testing and Development.

PKI Studio Family Dependencies

PKI Studio MCP imports the published PKI Studio family npm packages rather than vendoring their source:

• @pkistudio/pkistudiojs
• @pkistudio/certgadgets
• @pkistudio/pvkgadgets
• @pkistudio/asn1instancebuilder
• @pkistudio/asn1defsifter

Keep these dependencies aligned with the latest compatible PKI Studio family releases when updating MCP tool coverage or documentation.

License

PKI Studio MCP is licensed under the MIT License. See LICENSE.