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Validates PESEL/NIP/REGON/IBAN/Luhn/ISBN/EAN/SWIFT-BIC/VAT; RPN calc, date math, hashing, tokens
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Validates PESEL/NIP/REGON/IBAN/Luhn/ISBN/EAN/SWIFT-BIC/VAT; RPN calc, date math, hashing, tokens
Server tool list (30)
Raw names from tools/list. Only developers need these.
| datemath_add | Adds years/months/days to date. years/months are applied together with end-of-month clamping — e.g. 2026-01-31 + 1 month = 2026-02-28, not an overflowed 2026-03-03. days is then applied as plain calendar-day arithmetic. |
| datemath_age | Age in whole years as of asOf (optional, defaults to the current UTC date). A Feb-29 birthDate is treated as falling on March 1 in a non-leap asOf year. |
| datemath_businessdays | Counts days in [from, to] (inclusive on both ends) whose weekday is in weekdays (default mon-fri) and which aren't in holidays. |
| datemath_dayofweek | Day of the week for date: both the weekday name and its ISO 8601 weekday number (1=Monday..7=Sunday). |
| datemath_diff | Day difference between two YYYY-MM-DD dates: to minus from, in whole days. Negative if to is before from. |
| datemath_leapyear | Checks whether year is a leap year in the Gregorian calendar. |
| ean_validate | Validates an 8-digit (EAN-8), 12-digit (UPC-A), 13-digit (EAN-13), or 14-digit (GTIN-14) barcode checksum: alternating weights 1 3 applied right-to-left, check digit is (10 - sum mod 10) mod 10. |
| email_validate | Checks value is a single, bare RFC 5322 email address — syntax only, not a deliverability check. user@localhost is valid (no TLD required). "Name <email>" display syntax is rejected. |
| hash_digest | Computes a hash digest of input (decoded per encoding: "text" default, "base64", or "hex") using algo: md5, sha1, sha256, sha512, or crc32. Returns the digest as lowercase hex. |
| iban_validate | Validates an IBAN's length for its issuing country (per the SWIFT IBAN registry) and its mod-97 checksum. Does not decompose the BBAN into a bank code/account number or resolve a BIC. |
| isbn_validate | Validates a 10- or 13-character ISBN. ISBN-10 uses weights 10..1 over 10 characters (last may be X, worth 10), sum mod 11 must be 0. ISBN-13 uses the same GTIN checksum as barcodes. |
| jsonschema_validate | Validates document against schema (JSON Schema draft-07 or 2020-12). Reports one specific violation per call, not an aggregated list. |
| luhn_validate | Validates a numeric string against the Luhn (mod-10) checksum — payment card numbers, IMEI numbers, and similar identifiers. |
| nip_validate | Validates the checksum of a 10-digit Polish tax identification number (NIP). Checksum uses weights 6 5 7 2 3 4 5 6 7 over the first 9 digits; sum mod 11 must equal the 10th digit. A sum mod 11 of 10 is itself invalid. |
| pesel_validate | Validates the checksum of an 11-digit Polish national identification number (PESEL). Checksum uses weights 1 3 7 9 1 3 7 9 1 3 over the first 10 digits; control digit is (10 - sum mod 10) mod 10. On success also decodes the date of birth and sex embedded in the number; a checksum-valid number with an impossible calendar date (e.g. Feb 30) is still reported invalid. |
| random_int | Generates cryptographically random integers in [min, max] (inclusive), using crypto/rand — an actual random value, not a guess. count defaults to 1, max 1000. |
| regex_match | Tests input against pattern (Go's regexp package: RE2 syntax, not PCRE — no backreferences or lookaround; use inline flags like (?i) for case-insensitive matching). Returns the full match and captured groups. |
| regon_validate | Validates the checksum of a 9- or 14-digit Polish business registry number (REGON). 9-digit: weights 8 9 2 3 4 5 6 7 over the first 8 digits, sum mod 11 (10 mapped to 0) must equal the 9th digit. 14-digit: the first 9 digits must themselves be a valid 9-digit REGON, and weights 2 4 8 5 0 9 7 3 6 1 2 4 8 over the first 13 digits (sum mod 11, 10 mapped to 0) must equal the 14th digit. |
| rpncalc_eval | Evaluates a Reverse Polish Notation (postfix) expression: whitespace-separated tokens, each a number or an operator/function that pops its operands off a stack and pushes the result. Supports arithmetic, exponentiation/modulo, roots, trigonometry, logarithms, rounding, bitwise ops, and constants (pi, e, phi). Always returns the decimal result — for hex/bin/oct rendering, convert the returned number yourself. |
| swiftbic_validate | Structural format validation only for a SWIFT/BIC code: 8 or 11 characters (4 letters bank code + 2 letters country code + 2 alphanumeric location code + optional 3 alphanumeric branch code). The country code is not cross-checked against ISO 3166-1. |
| text_charat | Returns the 0-indexed character (rune) at index in text. |
| text_count | Counts non-overlapping occurrences of substring in text (rune-safe, not byte-based). |
| text_palindrome | Checks whether text reads the same forwards and backwards. ignoreCase/ignoreNonAlnum default false (strict, literal comparison); set both true for phrase-style palindromes like "A man, a plan, a canal: Panama". |
| text_reverse | Reverses text by Unicode code point (rune), not grapheme cluster. |
| text_sort | Sorts text's characters or words alphabetically. by: "chars" (default, sorts runes, no separator) or "words" (splits on whitespace, rejoins with a single space). |
| text_stats | Descriptive statistics for text: rune/byte/word/line counts, a unique-rune count, a letters/digits/spaces/punctuation/other breakdown, an exact per-character frequency table, and word-length min/max/average plus the actual shortest/longest word (ties resolve to the first occurrence). |
| text_wordcount | Counts whitespace-delimited words in text. |
| tokens_count | Counts tokens under an OpenAI-compatible (tiktoken) encoding. Provide exactly one of model (e.g. "gpt-4o") or encoding ("o200k_base" or "cl100k_base"). No Claude/Anthropic tokenizer. |
| url_validate | Checks value is a well-formed absolute URL (has both a scheme and a host) — syntax only, not a reachability check. |
| vateu_validate | Format validation only (no VIES lookup) for an EU VAT number: checks the 2-letter member-state prefix (EL for Greece, XI for Northern Ireland) against that country's digit/letter pattern. A format-valid result does not mean the number is actually registered. |