Dns class code lookup

dns-class-code-lookup · version 1.0.0 · Communications · free, no key needed

Look up a pinned DNS class mnemonic or its numeric code.

Use when you need to: dns class mnemonic to number · lookup dns rr class code · iana dns class code table.

Decide before calling

Read the versioned contract and the supported scope below. Reuse dns-class-code-lookup@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 dns-class-code-lookup@1.0.0 for dns class mnemonic to number. 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

• dns class mnemonic to number
• lookup dns rr class code
• iana dns class code table
• what number is the dns class in
• convert dns class name and code
• dns class code for in ch hs any
• איתור קוד מחלקת רשומת דיאן אס

Not supported

• encode or decode DNS RDATA
• choose a class for a zone
• query a DNS resolver

Behavior

• Provide exactly one of name or code. The pinned classes are IN 1, CS 2, CH 3, HS 4, NONE 254 and * 255. ANY is an alias of * and the returned name is *.
• query_only is true only for * (RFC 1035 QCLASS). NONE is reserved for RFC 2136 update prerequisites and updates, so query_only is false.
• A mnemonic or code outside the excerpt is unsupported_input. Lowercase text, an empty name, both fields, or neither field is invalid_input.
• data_version is iana-dns-parameters-2026-10-21. This tool does not encode RDATA and does not send a DNS query.
• More than 512 UTF-8 bytes of JSON input, or a name longer than 4 characters, is limit_exceeded.

Input

• name (string, optional): min length 1; max length 4
• code (integer, optional): min 0; max 65535

Output

• data_version (constant "iana-dns-parameters-2026-10-21", required)
• name (string, required): min length 1; max length 4
• code (integer, required): min 0; max 65535
• defining_document (string, required): min length 8; max length 12
• query_only (boolean, required)

Limits

• max input bytes: 512
• max name chars: 4

Example

Request input:

{
  "name": "IN"
}

Response:

{
  "result": {
    "data_version": "iana-dns-parameters-2026-10-21",
    "name": "IN",
    "code": 1,
    "defining_document": "RFC 1035",
    "query_only": false
  }
}

How to call it

MCP

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

{
  "id": "dns-class-code-lookup",
  "version": "1.0.0",
  "input": {
    "name": "IN"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/dns-class-code-lookup/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"name":"IN"}'

The machine-readable contract is at /v1/tools/dns-class-code-lookup/versions/1.0.0.

CLI

node cli.mjs run dns-class-code-lookup 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

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