Hash Utilities

Generate and verify hashes (MD5, SHA variants, CRC32, HMAC, BLAKE2) for strings and files with streaming support and no external dependencies.

Security Scan

The skill is internally coherent for a local hash/generate-and-verify utility — its code, README, and declared requirements mostly match the stated purpose, with a small Python version mismatch to note.

Purpose & Capability

The name, description, SKILL.md, and the included Python script all align: the skill computes and verifies hashes (MD5/SHA/CRC32/HMAC/BLAKE2) for strings and files. However, the SKILL.md claims 'Python 3.6+' while the code uses the walrus operator (':=') in file-read loops, which requires Python 3.8+. This is a mismatch between claimed runtime and actual code requirements.

Instruction Scope

SKILL.md only instructs how to hash strings/files, verify values, batch files, and generate HMACs. It does not ask the agent to read unrelated system files, environment variables, or send data to external endpoints. The CLI reads only user-specified file paths.

Install Mechanism

There is no install spec (instruction-only skill with an accompanying script). Nothing is downloaded or written during install according to metadata. The included code is pure-Python stdlib and does not require external packages.

Credentials

The skill requests no environment variables, no credentials, and no config paths. Its runtime uses only standard libraries (hashlib, hmac, zlib, binascii, os, argparse) which are appropriate for the stated functionality.

Persistence & Privilege

The skill is not marked always:true, does not request elevated/persistent presence, and does not modify other skills or system-wide configuration. Autonomous invocation is allowed by default but is not combined with any other concerning privileges.

Assessment

This appears to be a straightforward local hashing utility and is coherent with its description. Before installing or running it: (1) run it under a controlled environment (or inspect the repository link in SKILL.md) and ensure your runtime is Python 3.8+ (the code uses ':='); (2) only pass file paths or secrets you trust — the tool will read any file path you give it locally; (3) HMAC keys are used locally by the script — do not paste production secrets into an untrusted environment; and (4) if you need strict compatibility with Python 3.6–3.7, request or adapt a version of the code that avoids the walrus operator.

🔐 Hash Toolkit

Author: Lin Hui | GitHub | MIT License | v1.0.0

Compute and verify hashes for strings, files, and data. Supports MD5, SHA1, SHA256, SHA512, CRC32, HMAC, and BLAKE2.

✨ Features

• String hashing — Hash any text with your choice of algorithm
• File hashing — Compute hash of any file (streaming for large files)
• Verify — Compare a hash against expected value (pass/fail)
• Batch — Hash multiple files at once
• HMAC — Keyed-hash message authentication codes
• CRC32 — Quick checksums for data integrity
• BLAKE2 — Modern, fast, secure hash algorithm

🚀 Usage

Calculate the SHA256 hash of the string "hello world"

Compute the MD5 hash of the file /path/to/file.zip

Verify that the SHA256 hash of download.iso matches abc123def...

Generate HMAC-SHA256 signature for "message" with key "secret"

Calculate CRC32 checksum for data.bin

⚙️ Technical Details

• Runtime: Python 3.6+
• Dependencies: Zero (stdlib only: hashlib, hmac, zlib, binascii)
• Algorithms: MD5, SHA1, SHA224, SHA256, SHA384, SHA512, BLAKE2b, BLAKE2s, CRC32
• Large files: Streaming with 8MB chunks