Does this tool 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. Tools 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.

JWT Payload Extractor MCP Connector for Claude

A+

Extract and decode JWT payloads deterministically without cryptographic verification.

3 tools Official Updated Oct 1, 2026 Official Vinkius Partner

More Details Connect to Claude

The jwt-payload-extractor implements a deterministic decoding pipeline for inspecting JSON Web Token (JWT) payloads without cryptographic verification. The process begins by splitting the input string via the period delimiter to isolate the second segment. It then performs Base64URL normalization, specifically replacing hyphens (-) with plus signs (+) and underscores (_) with forward slashes (/), before applying standard Base64 decoding via atob. This allows for the extraction of claims such as 'sub', 'iat', or custom identifiers. The server also facilitates temporal analysis by parsing the 'exp' claim and comparing its Unix timestamp against the current system clock to determine token validity.