High-risk tools in ScorpTech x402 API

Build EVM calldata offline: function selector + ABI-encoded arguments from a human signature such as transfer(address,uint256) or exactInputSingle((address,address,uint24,addres...

One summand of the Apery number, C(n,k)^2 * C(n+k,k)^2. The k=1 summand of A(2) is 36 and the k=0 summand is 1. A k past n is 0. n and k run from 0 to 11. Price: $0.001 USDC per...

The ballot number B(n, k) = (n-k+1)/(n+1) * binom(n+k, k), for 0 <= k <= n. B(n, n) is the nth Catalan number. k above n is rejected. Both indexes run up to 2048. Price: $0.001 ...

The Baum-Sweet bit of n. It is 1 when every run of 0s in the binary expansion has even length, and 0 when some run of 0s has odd length. b(0) is 1 and b(2) is 0. n runs from 0 t...

The binomial coefficient C(n, k). k must not exceed n, and both indexes run up to 4096. An optional modulus reduces the coefficient; zero is rejected. Past 15 digits the value i...

Whether every 1 bit of a is also a 1 bit of b. 3 is a bit-subset of 7. 3 is not a bit-subset of 5. 0 is a bit-subset of 0. Both run from 0 to 999999999999999. Price: $0.001 USDC...

The sum of the bi-unitary divisors of n. For a prime power p^e the exponents run from 0 through e, skipping the middle one when e is even. 6 gives 12, 16 gives 27, 36 gives 50, ...

The first Champernowne place occupied by the integer m. 1 starts at 1, 10 starts at 10, 11 starts at 12, and 100 starts at 190. m runs from 1 to 999999999999. Price: $0.001 USDC...

Search ClinicalTrials.gov (API v2) by condition, keyword, location, sponsor, recruitment status (or open/closed) and phase. Returns NCT id, title, status, phases, study type, co...

The fewest coins of denominations a and b that sum to n. Making 10 with 2 and 5 takes 2 coins. An amount that cannot be made is rejected. a and b run from 1 to 10000, and n runs...

The number of non-negative integer solutions of a*x + b*y = n. Order of summands does not matter. There are 2 ways to make 10 with 2 and 5, and 0 ways to make 3. a and b run fro...

Generate colour palettes from one base colour: complementary, analogous, triadic, split-complementary, tetradic and monochromatic schemes plus an 11-step 50-950 shade scale (Tai...

Compound growth / savings calculator: future value of a principal plus monthly contributions at any compounding frequency (incl. continuous), contributions at start or end of mo...

Explain a standard 5-field cron expression in plain English and list its next N run times (default 5, max 20) in any IANA zone, DST-correct. Supports lists, ranges, steps (*/n, ...

Convert a curl command (copied from browser dev tools, API docs or a terminal) into ready-to-run code: Python requests, JavaScript fetch, Node axios, Go net/http, PHP curl, Rust...

Calendar-correct date arithmetic in any IANA zone: add or subtract durations (ISO 8601 or plain English, months clamp to month end so Jan 31 + 1 month = Feb 28/29), exact differ...

The Delannoy number D(m,n), the number of paths from (0,0) to (m,n) using steps (1,0), (0,1), and (1,1). D(3,5) is 231. m and n run from 0 to 64. Past 15 digits the value is a d...

The sum of Delannoy numbers D(m,0) through D(m,hi). The sum through D(4,4) is 501. m and hi run from 0 to 64. Past 15 digits the sum is a decimal string. Price: $0.001 USDC per ...

Parse DMARC aggregate (RUA) reports and SMTP TLS reports (TLS-RPT, RFC 8460) into an actionable summary. Accepts the raw XML / JSON or the email attachment as base64 (.xml, .xml...

Offline Dockerfile linter: parses stages/continuations and runs 20+ best-practice and security rules (latest tag, curl|bash, secrets in ENV/ARG, runs-as-root, chmod 777, ADD-vs-...

One summand of the Domb number, C(n,k)^2 * C(2k,k) * C(2n-2k,n-k). The k=1 summand of D(2) is 16 and the k=0 summand of D(3) is 20. A k past n is 0. n and k run from 0 to 12. Pr...

Parse any duration into seconds and every common format: ISO 8601 (P1DT2H30M, PT1.5S, P2W), clock (1:02:03.5, 02:30), Go / compact (1h30m, 2d4h), and plain English ("an hour and...

Recent earthquakes from the USGS: filter by bounding box or center point + radius, minimum magnitude and time window (last N days or start/end dates). Returns magnitude, place, ...

The greedy Egyptian-fraction denominators of a/b, written comma-separated. 3/7 gives 3,11,231. 5/6 gives 2,3. 1/2 gives 2. The fraction must be proper. a and b run from 1 to 30,...

The first denominator in the greedy Egyptian expansion of a/b. 3/7 starts at 3, 5/6 starts at 2, and 2/3 starts at 2. The fraction must be proper. a and b run from 1 to 30, with...

The last denominator in the greedy Egyptian expansion of a/b. 3/7 ends at 231, 8/11 ends at 4070, and 1/2 ends at 2. The fraction must be proper. a and b run from 1 to 30, with ...

How many unit fractions the greedy Egyptian expansion of a/b uses. 1/2 uses 1, 5/6 uses 2, 3/7 uses 3, and 8/11 uses 4. The fraction must be proper. a and b run from 1 to 30, wi...

The sum of the denominators in the greedy Egyptian expansion of a/b. 3/7 sums to 245, 5/6 sums to 5, and 8/11 sums to 4114. The fraction must be proper. a and b run from 1 to 30...

Parse a raw email (.eml / RFC 5322 + MIME) for triage: decoded headers (RFC 2047), addresses, Received hop chain with relays, IPs, timestamps and delays, originating IP, Authent...

The Entringer number E(n, k). E(1, 1) is 1, and E(n, k) = E(n, k-1) + E(n-1, n-k). E(5, 2) is 10, and E(6, 3) is 46. The last entry E(n, n) is the zigzag number a(n). n and k ru...

FIRST EPSS exploit-prediction scores for up to 100 CVEs: probability of exploitation in the next 30 days, percentile rank and a simple band, for the latest model run or a past d...

Explain a POSIX file mode. Accepts octal (755, 0755, 4755) or the 9-character ls form, with an optional leading type character. s and t mean the execute bit is also set; S and T...

Geodesic distance and bearings on the WGS-84 ellipsoid: Vincenty (millimetre accuracy) plus great-circle haversine, initial / final bearing with 16-point compass, midpoint, mult...

Security audit of a GitHub Actions workflow YAML (zizmor / actionlint style): pwn-request checkouts under pull_request_target / workflow_run, script injection from attacker-cont...

The Hamming distance of a and b: how many bit positions differ. 13 and 7 differ in 2 places. 0 and 0 differ in none. Both run from 0 to 999999999999999. Price: $0.001 USDC per s...

The hockey-stick sum of binomial coefficients C(i, r) from i = r through n. It equals C(n+1, r+1). The sum for r = 2 and n = 5 is 20. r must not pass n. Both run from 0 to 1024....

Parse an iCalendar (.ics) feed from a URL (SSRF-safe; Google / Outlook / Apple calendar exports) or inline text into JSON: calendar name and zone, events with start / end in any...

The surviving seat in the Josephus circle. Seats are 1 through n, counting starts at 1, and every k-th remaining person leaves. 5 people and every 2nd leave seat 3. 41 people an...

The Kolakoski run that contains the 1-based index n. A run has length 1 or 2. Index 1 is a single 1. Index 2 starts two 2s. n runs from 1 to 100000. Price: $0.001 USDC per succe...

The Kronecker symbol (a/n) for any integers a and n. (2/7) is 1, (3/7) is -1, (2/4) is 0, and (1/0) is 1. Both a and n run from -1000000000000 to 1000000000000. Price: $0.001 US...

The number of carries when a and b are added in prime base p. By Kummer, that is the exponent of p in C(a+b, a). Adding 5 and 3 in base 2 makes 3 carries. A composite base is re...

The unsigned Lah number L(n, k). L(0, 0) is 1, L(n, 0) is 0 for n > 0, and L(n, 1) is n!. L(5, 2) is 240, and L(6, 3) is 1200. n and k run from 0 to 20, and k must not pass n. P...

The Leyland number x^y + y^x. 2 and 2 give 8, 2 and 3 give 17, and 3 and 3 give 54. x and y each run from 2 to 20. Past 15 digits the value is a decimal string. Price: $0.001 US...

The nth look-and-say term, starting from 1. Term 1 is 1, term 4 is 1211, and term 5 is 111221. Each run of k copies of a digit d becomes the digits of k followed by d. n runs fr...

Whether n and n+2 are both lucky. 1, 7, and 13 start a lucky pair. 3 does not, because 5 is not lucky. n runs from 1 to 99985. Price: $0.001 USDC per successful call (x402, Sola...

Build or parse Markdown (GitHub-flavoured) tables. Build: from an array of objects, an array of arrays or CSV, with column selection / order / renaming, alignment (numeric colum...

Bits that differ between two POSIX modes. added and removed run from the special bits down through owner, group and other. same is true when nothing differs. Price: $0.001 USDC ...

The Thue-Morse run that contains n. The bit is the parity of the 1-bits of n. A run has length 1 or 2. Index 0 is a run of one 0, and index 1 starts a run of two 1s. n runs from...

The number of ways to choose k elements from n types with repetition, which is C(n+k-1, k). Choosing 2 from 3 types can be done in 6 ways. Choosing nothing can be done in 1 way....

Spell a scale on letters from a tonic. Major, minor, harmonic minor, melodic minor (the ascending form), the church modes, pentatonic, minor pentatonic, and blues. G# major is w...

The nim-sum of a and b, their bitwise exclusive or. 13 xor 7 is 10, and 255 xor 256 is 511. Both run from 0 to 999999999999999. Price: $0.001 USDC per successful call (x402, Sol...

OAuth 2.0 PKCE helper (RFC 7636 / OAuth 2.1): generate a code_verifier with its S256 code_challenge plus random state and OIDC nonce, verify that a verifier matches a challenge,...

The largest scale that places one sheet on another, turning it when that lets it be larger. The scale is an exact ratio of the millimeter sides. Below one, the sheet has to shri...

Whether n is y-power-smooth: every maximal prime-power factor p^k is at most y. 12 is 4-power-smooth and not 3-power-smooth. 8 is 8-power-smooth and not 4-power-smooth. n and y ...

Prorate a money amount across a date range, in exact cents. The window is half-open: from the start date up to but not including the end date. The charge is amount × days used /...

The tree edges for a Prüfer code, as a flat list of sorted pairs. Code 2,3 is the path 1-2-3-4. Code 1,1 is the star at 1. An empty code is the edge 1-2. Code entries run from 1...

The Prüfer code of a tree on vertices 1..n. Edges are a flat list of pairs. The path 1-2-3-4 gives 2,3. The star with center 1 and leaves 2,3,4 gives 1,1. Two vertices give an e...

The Pythagorean triple from m > n >= 1 and scale k >= 1. a is k(m^2-n^2), b is k(2mn), and c is k(m^2+n^2). primitive is true when k is 1, m and n are coprime, and they have opp...

Provably fair random draws for giveaways, raffles, games and A/B assignment. Pick winners from a list (unique or with replacement, optional weights), shuffle a list, split peopl...

Fit a regression model and get the full statistical table, like R's summary(lm) or statsmodels. Linear, polynomial (degree 2–6), exponential (y = a·e^(bx)), logarithmic, power (...

IEC 60062 resistor color code. Decode 3 to 6 bands, or encode a resistance that lands exactly on a digit-and-multiplier value. Digits run black=0 through white=9. Multipliers ru...

Whether n is y-rough: its smallest prime factor is at least y. 35 is 5-rough and not 7-rough. 1 is 1-rough and not 2-rough. n and y run from 1 to 1000000000000. Price: $0.001 US...

Whether n is y-smooth: its largest prime factor is at most y. 12 is 3-smooth and not 2-smooth. 1 is 1-smooth. n and y run from 1 to 1000000000000. Price: $0.001 USDC per success...

The Stirling number of the second kind S(n,k), the number of ways to partition n objects into k nonempty unlabeled sets. S(5,2) is 15. S(n,k) is 0 when k is greater than n. n an...

The Stirling recurrence S(n,k) = k*S(n-1,k) + S(n-1,k-1). term is the first summand and diag is the second. n and k run from 1 to 80. Past 15 digits a part is a decimal string. ...

Split text into retrieval-ready chunks for RAG and embeddings: recursive (paragraph > line > sentence > clause > word), markdown-aware (splits on headings, keeps the heading pat...

Largest Helvetica size, on a fixed step, at which one line still fits a width. Sizes run from minSize to maxSize in steps (defaults 6, 72 and 0.5 points). Empty text fits at max...

Parse, normalize and clean URLs offline: scheme, credentials (redacted), host type, port, path segments, decoded query parameters and fragment; registrable domain / subdomain / ...

Federal contracts, IDVs, grants, loans and direct payments from USAspending.gov by recipient, awarding agency (name or abbreviation such as DOD, NASA, HHS), NAICS code or keywor...

Parse User-Agent strings: browser and version, rendering engine, OS and version, device type (mobile, tablet, desktop, TV, console, bot) with vendor/model, and bot detection tha...

The Vandermonde convolution. The sum of C(m, k)*C(n, r-k) equals C(m+n, r). For m = 3, n = 3, and r = 2 the value is 15. m and n run from 0 to 256, and r must not pass m+n. Pric...

Run XPath 1.0 queries over XML you supply (RSS/Atom, SOAP, sitemaps, SVG, config) or over HTML for scraping: returns matched elements/attributes/text with their paths, text, att...

The Zeckendorf representation of n. Fibonacci numbers start F1 = 1, F2 = 1, F3 = 2, and no two used indices are consecutive. 4 is F4 + F2, and 100 is F11 + F6 + F4. n runs from ...