Does this MCP verify the JWT signature?

No. This MCP is designed for deterministic decoding of the payload only. It does not perform cryptographic verification of the signature.

What clients can use this MCP?

You can use this with any MCP-compatible client, including Claude, Cursor, Windsurf, and VS Code.

Can I extract specific claims?

Yes. You can use the extract_token_identity capability to pull specific values like user IDs or roles from the payload.

How does it check for expired tokens?

The check_token_expiry capability parses the 'exp' claim and compares that Unix timestamp to the current system time.

Do I need to host this myself?

No. Vinkius hosts and manages the MCP for you. You just connect your client and start using the capabilities.

Does this capability verify the JWT signature?

No, the server focuses exclusively on the deterministic parsing of the payload segment. It does not utilize any cryptographic primitives or secret keys to validate the integrity of the signature segment. Capabilities available: decode_jwt_payload, check_token_expiry, extract_token_identity.

How can I see the expiration date of a token?

The server extracts the 'exp' claim from the decoded JSON object and compares its Unix timestamp against the current system time to identify if the token's operational window has expired.

Can I extract specific user IDs from the token?

Yes. After parsing the payload segment into a JSON structure, the server traverses the object hierarchy to retrieve the value associated with any specified key, such as 'sub' or custom user identifiers.

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Connect JWT Payload Extractor to ChatGPT, Claude and Gemini

Set it up once and it works in ChatGPT, Claude, Cursor, and any other client you love. It all runs safely in the background, so you can relax and focus on what really matters. Inspect token claims and expiration without cryptographic overhead.

Ask AI about this Connector

Developed, maintained, and hosted by Vinkius.

MCP VERIFIED · PRODUCTION READY · VINKIUS GUARANTEED

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Works with modern AI clients that support MCP, including ChatGPT, Claude, Cursor, and more.

Your AI does the work. We keep it safe and sound.

No other AI tool gives you this. Your workflow runs in the client you already love, your account stays protected, and you decide what the agent can and cannot do. It is the whole reason to make the switch.

Each Connector lives inside our infrastructure, the same place where your workflow runs. The three things below are already part of it, working quietly in the background so you never have to think about them. Nothing to add, nothing to set up, nothing to worry about.

V8 Isolate01

Each Connector runs inside its own sealed environment.

Each Connector runs inside its own sealed V8 runtime — no access to your files, your system, or other servers. A Connector never sees past its own request.

Kill Switch02

One switch stops every agent. Instantly.

One action deactivates every Connector, revokes every token, and ends every session at once. AI Governance keeps the record.

FinOps per User03

Spending limits that pause instead of surprise.

Every user keeps their own connections and credentials, isolated from everyone else. Anything that would cross your spending limit is held for your approval, not billed.

Three controls, built into the layer your AI connects through.

Curated set · 3 capabilities

We ship only the actions that matter.

Capability set01 / 01

01-03

3 capabilities in this set.

Part of 3 available through JWT Payload Extractor.

01
Extract token identity
This capability pulls a specific identity claim from a JWT. Use it to grab things like user IDs or custom identifiers.
02
Check token expiry
This capability checks if a JWT is still valid. It compares the expiration timestamp in the payload against the current time.
03
Decode jwt payload
This capability decodes the entire payload segment of a JWT string. It turns the Base64URL encoded data into a readable format.

Real work

What teams actually run

Debugging Auth Flows

Paste a token from a browser console to see why a user is being denied access.

Validating Claims

Check if a specific role or permission is correctly encoded in a token.

Session Monitoring

Verify if a token has passed its expiration time.

Data Mapping

Identify the structure of custom claims within a third party JWT.

One connector, every AI

JWT Payload Extractor works with the most popular AI clients.

These are the most popular clients, each with a step-by-step guide: one link, set up once, with governance and visibility built in. And because everything runs on the MCP standard, the same connection also works in any other compatible client — nothing to rebuild.

Building your own app? The connector is yours to use.

You don't need a client to put JWT Payload Extractor to work: the same hosted connection plugs into your own applications and agent code, with the same governance on every request. Build with it, chat with it — one connection for both.

Observed, not estimated

681ms average. Fast in production.

JWT Payload Extractor is checked daily against the live service.

Daily averagePeak 843ms

Oct 3Today

Fastest day: 538ms
Slowest day: 843ms
14-day trend: Stable-4%

Connect your client

One URL. Every client.

Activate the Connector, copy your link, and paste it into the client you already use. 3 capabilities arrive ready to run.

Preview access · not provider authentication

The vk_preview_* token belongs to Vinkius preview infrastructure. It lets Claude discover and display the capabilities of JWT Payload Extractor, so you can see the experience inside your AI.

It does not authenticate your account with JWT Payload Extractor. Actions requiring credentials or live account data may not run until you activate the Connector and authorize the service.

JWT Payload Extractor Connector

You're all set. Choose your MCP client and follow the setup instructions.

Connector linkhttps://edge.vinkius.com/vk_preview_ZDWvfAAQYs5wuqUcHTycNIaN4acsQhRWK43rr8eY/mcp

Claude Desktop

Follow the steps below to connect in seconds.

1In Claude Desktop, open Settings → Connectors.
2Click “Add custom connector” and paste the connector link above as the remote MCP server URL.
3Click Add and start a new chat — JWT Payload Extractor capabilities are ready to use.

Configuration · claude_desktop_config.jsonCopy

{
  "mcpServers": {
    "jwt-payload-extractor-mcp": {
      "url": "https://edge.vinkius.com/vk_preview_ZDWvfAAQYs5wuqUcHTycNIaN4acsQhRWK43rr8eY/mcp"
    }
  }
}

Claude
ChatGPT
Cursor
VS Code
Windsurf
Claude Code
JetBrains
Cline

Step-by-step instructions for each client are in the guide. How to connect

Guided setup for Claude? Set up JWT Payload Extractor in Claude and other AIs

See all the AI clients this connector works with ↑

Who it's for

Built for the work JWT Payload Extractor owners hand off.

This MCP is built for developers working with authentication and identity management.

01
Backend Developers
They hand off raw JWT strings to the AI to debug user claims or session issues.
02
Security Engineers
They use the capability to quickly inspect token contents during security audits.
03
QA Engineers
They use it to verify that tokens contain the expected data during automated testing.

FAQ

Questions JWT Payload Extractor owners ask.

01
Does this MCP verify the JWT signature?
No. This MCP is designed for deterministic decoding of the payload only. It does not perform cryptographic verification of the signature.
02
What clients can use this MCP?
You can use this with any MCP-compatible client, including Claude, Cursor, Windsurf, and VS Code.
03
Can I extract specific claims?
Yes. You can use the extract_token_identity capability to pull specific values like user IDs or roles from the payload.
04
How does it check for expired tokens?
The check_token_expiry capability parses the 'exp' claim and compares that Unix timestamp to the current system time.
05
Do I need to host this myself?
No. Vinkius hosts and manages the MCP for you. You just connect your client and start using the capabilities.
06
Does this capability verify the JWT signature?
No, the server focuses exclusively on the deterministic parsing of the payload segment. It does not utilize any cryptographic primitives or secret keys to validate the integrity of the signature segment. Capabilities available: decode_jwt_payload, check_token_expiry, extract_token_identity.
07
How can I see the expiration date of a token?
The server extracts the 'exp' claim from the decoded JSON object and compares its Unix timestamp against the current system time to identify if the token's operational window has expired.
08
Can I extract specific user IDs from the token?
Yes. After parsing the payload segment into a JSON structure, the server traverses the object hierarchy to retrieve the value associated with any specified key, such as 'sub' or custom user identifiers.

Explore

More in Developer Tools

Connect JWT Payload Extractor to Claude, Cursor, ChatGPT & more

Your AI does the work. We keep it safe and sound.

Each Connector runs inside its own sealed environment.

One switch stops every agent. Instantly.

Spending limits that pause instead of surprise.

We ship only the actions that matter.

01-03

Extract token identity

Check token expiry

Decode jwt payload

What teams actually run

Debugging Auth Flows

Validating Claims

Session Monitoring

Data Mapping

Building your own app? The connector is yours to use.

JWT Payload Extractor Connector

Claude Desktop

Backend Developers

Security Engineers

QA Engineers

Does this MCP verify the JWT signature?

What clients can use this MCP?

Can I extract specific claims?

How does it check for expired tokens?

Do I need to host this myself?

Does this capability verify the JWT signature?

How can I see the expiration date of a token?

Can I extract specific user IDs from the token?

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