mcpField
J
Jwt

Jwt

Remote
pipeworx.ioDeveloper Tools0Updated 5w ago

About Jwt

Jwt is a lightweight MCP server for developers who need to inspect JSON Web Tokens. It decodes headers, payloads, and standard claims offline without verifying signatures.

Key features

  1. 01Offline JWT decoding
  2. 02Header and payload JSON
  3. 03Standard claims with ISO dates
  4. 04Expired-token status

Use cases

  1. 01Inspect a token's claims
  2. 02Check token expiration
  3. 03Review JWT headers and payloads

MCP support

Exposes `decode_jwt` as an MCP tool. It can run through the Pipeworx gateway or as a local stdio server; decoding does not verify the token signature.

Configuration

Remote servers need no local install. Pick your client, then copy the config or install in one click.

Endpointhttps://gateway.pipeworx.io/jwt/mcp
Copy install command
Claude CodeTerminal
Cursor.cursor/mcp.json
VS Code.vscode/mcp.json
Claude Desktopclaude_desktop_config.json
Windsurf~/.codeium/windsurf/mcp_config.json

Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.

Tools

Details

From the project README

mcp-jwt

JWT decoder MCP.

Part of Pipeworx — an MCP gateway connecting AI agents to 1679+ live data sources.

Tools

ToolDescription
decode_jwtDecode a JSON Web Token (keyless, offline): returns the header and payload JSON plus a summary of the standard claims (iss, sub, aud, exp/iat/nbf as ISO dates, and whether it is expired). NOTE: this decodes but does NOT verify the signature — a decoded token is not a verified/trusted token.

Quick Start

Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):

{
  "mcpServers": {
    "jwt": {
      "url": "https://gateway.pipeworx.io/jwt/mcp"
    }
  }
}
What this endpoint actually serves

tools/list at https://gateway.pipeworx.io/jwt/mcp returns the tools in the table above plus the shared Pipeworx meta-tools — ask_pipeworx, discover_tools, search_within, remember/recall and the rest of the gateway-wide set. So the tool count you see is larger than this table: a single-pack endpoint currently lists roughly 30 shared tools alongside the pack's own. The connection's initialize response states its exact scope, and is the authoritative answer for a given day.

This is deliberate, not multiplexing by accident. The meta-tools are what let a scoped connection answer a question this pack does not cover — via ask_pipeworx, which routes across the whole catalog — without you adding a second MCP server. There is currently no way to mount a pack endpoint without them; if the extra schemas cost you more context than the routing is worth, connect to the full gateway once rather than to several pack endpoints.

Or connect to the full Pipeworx gateway to get every pack's tools listed directly, instead of just this one's:

{
  "mcpServers": {
    "pipeworx": {
      "url": "https://gateway.pipeworx.io/mcp"
    }
  }
}

Both URLs reach the same gateway and the same 1679+ data sources. The only difference is which pack's tools are listed directly; ask_pipeworx reaches all of them from either one.

No MCP client? Call it over HTTP

curl -X POST https://gateway.pipeworx.io/v1/tools/decode_jwt \
  -H 'Content-Type: application/json' \
  -d '{"token":"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"}'

No account needed for the first calls. Inspect any tool: GET https://gateway.pipeworx.io/v1/tools/decode_jwt. Find one: POST https://gateway.pipeworx.io/v1/tools/search_packs with {"query":"..."}.

Standalone (no gateway account)

This package also runs as a local stdio MCP server — no Pipeworx account, no gateway round-trip:

{
  "mcpServers": {
    "jwt": {
      "command": "npx",
      "args": ["-y", "@pipeworx/mcp-jwt"]
    }
  }
}

Or run it directly to confirm it starts:

npx -y @pipeworx/mcp-jwt

It speaks MCP over stdin/stdout and answers initialize/tools/list/tools/call for only this pack's tools — none of the shared meta-tools the gateway connection above adds. Same source, same tools, no ask_pipeworx routing.

Using with ask_pipeworx

Instead of calling tools directly, you can ask questions in plain English — this works on the pack endpoint above as well as on the full gateway:

ask_pipeworx({ question: "your question about Jwt data" })

The gateway picks the right tool and fills the arguments automatically.

More

License

MIT

Comments

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New to MCP?

From what the protocol is to installing your first server, these answers cover most first questions.

An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.