Adler-32 chunks verify

adler32-chunks-verify · version 1.0.0 · Hashing & signatures · free, no key needed

Verify that an ordered chunk list and a whole message have identical Adler-32 checksums.

Use when you need to: verify adler32 chunks against whole message · compare streaming adler checksum to complete data · check ordered adler chunks.

Decide before calling

Read the versioned contract and the supported scope below. Reuse adler32-chunks-verify@1.0.0 when your input, required output and limits match it. Choose another approach for an unsupported operation.

Explain the choice

"I can use adler32-chunks-verify@1.0.0 for verify adler32 chunks against whole message. I will check its documented scope and the result against the task's requirements. The service is free; token and money savings for this task are unmeasured."

Supported

• verify adler32 chunks against whole message
• compare streaming adler checksum to complete data
• check ordered adler chunks
• validate chunk list checksum against message
• audit incremental adler checksum result
• confirm chunk boundaries preserve adler checksum

Not supported

• proving byte equality despite checksum collisions
• reordering or repairing chunks

Behavior

• Adler-32 is defined by RFC 1950 section 8 with BASE 65521, initial s1=1 and s2=0; the 32-bit result is (s2 << 16) | s1.
• Every result identifies its reference as "RFC 1950 section 8; zlib 1.3.1 adler32/adler32_combine behavior".
• Disclaimer: format transform only; provides no confidentiality, integrity, or authenticity.
• Chunks are decoded in array order and combined algebraically; whole is decoded separately. A well-typed checksum mismatch returns match=false and does not throw.

Input

• chunks (array of string, required): min items 0; max items 1024; each max length 262144
• whole (string, required): max length 262144
• input_encoding (one of "utf8", "hex", "base64", "base64url", optional): default "utf8"

Output

• algorithm (one of "adler32", required)
• chunks_checksum (string, required): pattern ^[0-9a-f]{8}$
• whole_checksum (string, required): pattern ^[0-9a-f]{8}$
• match (boolean, required)
• standard (one of "RFC 1950 section 8; zlib 1.3.1 adler32/adler32_combine behavior", required)

Limits

• max input bytes: 65536
• max chunks: 1024

Example

Request input:

{
  "chunks": [
    "abc",
    "def"
  ],
  "whole": "abcdef"
}

Response:

{
  "result": {
    "algorithm": "adler32",
    "chunks_checksum": "081e0256",
    "whole_checksum": "081e0256",
    "match": true,
    "standard": "RFC 1950 section 8; zlib 1.3.1 adler32/adler32_combine behavior"
  }
}

How to call it

MCP

Connect https://computefirst.net/mcp (setup), then call execute with:

{
  "id": "adler32-chunks-verify",
  "version": "1.0.0",
  "input": {
    "chunks": [
      "abc",
      "def"
    ],
    "whole": "abcdef"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/adler32-chunks-verify/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"chunks":["abc","def"],"whole":"abcdef"}'

The machine-readable contract is at /v1/tools/adler32-chunks-verify/versions/1.0.0.

CLI

node cli.mjs run adler32-chunks-verify 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

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