File Hasher

Compute, verify, and compare file hashes using MD5, SHA-1, SHA-256, SHA-512, and more. Use when checking file integrity, verifying downloads against expected...

Security Scan

The skill does what its name/description promise — a local file hashing and verification tool that operates on files you specify and does not request credentials or network access.

Purpose & Capability

Name/description (file hashing, verify/compare checksums) matches the included instructions and the script. The required capabilities (reading files, walking directories, computing hashes) are appropriate and proportional.

Instruction Scope

SKILL.md instructs running the included Python script with file paths and options; the script's operations are limited to local filesystem reads and hashing. It does not read unrelated configuration, environment variables, or contact external endpoints in the visible code.

Install Mechanism

No install spec — instruction-only with an included script. This is low-risk: nothing is downloaded or installed automatically.

Credentials

The skill requires no environment variables, credentials, or config paths. The code does not access os.environ or other secrets in the visible portion.

Persistence & Privilege

Skill is not marked always:true, does not request persistent elevated privileges, and does not modify other skills or system-wide config (based on the provided files).

Assessment

This skill appears coherent and self-contained: it computes and verifies hashes of files you explicitly provide and does not request credentials or network access. Before installing or running it, you may (1) review the full, untruncated script to confirm there are no unexpected network calls or subprocess.exec usage, (2) run it in a limited environment (or sandbox) the first time, and (3) verify the script path (scripts/file_hasher.py) is what you expect. If you need absolute assurance, run a static scan of the full file and/or execute it on non-sensitive sample files first.

Compute, verify, and compare file hashes. Supports all hashlib algorithms. Zero dependencies.

Quick Start

# Hash a file (SHA-256)
python3 scripts/file_hasher.py hash myfile.txt

# Verify a download
python3 scripts/file_hasher.py verify image.iso -e abc123def456...

# Compare two files
python3 scripts/file_hasher.py compare file1.txt file2.txt

Commands

hash

Compute file hash with one or more algorithms:

python3 scripts/file_hasher.py hash file.txt                        # SHA-256
python3 scripts/file_hasher.py hash file.txt -a md5                 # MD5
python3 scripts/file_hasher.py hash file.txt -a md5,sha1,sha256     # Multiple
python3 scripts/file_hasher.py hash *.py --bsd                      # BSD format
python3 scripts/file_hasher.py hash data.bin --json                 # JSON output

verify

Check a file against an expected hash:

python3 scripts/file_hasher.py verify image.iso -e <expected_hash>
python3 scripts/file_hasher.py verify file.tar.gz -e <hash> -a sha512

Exit code 0 = match, 1 = mismatch.

check

Verify files from a checksum file (sha256sum/md5sum/BSD format):

python3 scripts/file_hasher.py check SHA256SUMS
python3 scripts/file_hasher.py check checksums.txt -a md5

Auto-detects algorithm from hash length and BSD format headers.

compare

Compare two files by hash:

python3 scripts/file_hasher.py compare original.bin copy.bin
python3 scripts/file_hasher.py compare a.txt b.txt -a md5

directory

Hash all files in a directory:

python3 scripts/file_hasher.py directory ./src                  # Top level
python3 scripts/file_hasher.py directory ./project -r           # Recursive
python3 scripts/file_hasher.py directory ./dist -r --bsd -a md5 # BSD + MD5

string

Hash a text string directly:

python3 scripts/file_hasher.py string "hello world"
python3 scripts/file_hasher.py string "password" -a md5,sha256,sha512

algorithms

List all available hash algorithms:

python3 scripts/file_hasher.py algorithms