the402 x402 endpoint directory

Arithmetic mean of numbers. Call when summarizing metrics, scores, or sensor lists mid-pipeline. Returns the mean of a

Nth Fibonacci (n≤78). Use for sequences, demos, or test fixtures without shipping a math package. Returns F(n) for n u

Factorial (n≤20). Call for combinatorics demos and small counting problems with an explicit n cap. Returns n! for n up

Prime factorization. Use when agents need factorization for puzzles, crypto teaching, or ratio breakdowns (bounded n).

Primality check. Call for teaching demos, ID heuristics, or lightweight number filters (bounded integers). Returns whe

Least common multiple. Use for cadence alignment, tile sizes, or schedule math in agent workflows. Returns LCM of two

Greatest common divisor. Handy for ratio simplification, scheduling grids, or math agents without local bigint helpers

Normalize phone to digits. Use before SMS gateways, CRM writes, or dedupe on contact fields. Returns digits-only phone

Time-sortable IDs. Use when you want roughly time-ordered IDs for logs or event streams without a DB sequence. Returns

NanoID-style public IDs. Generate short URL-safe IDs for jobs, drafts, or idempotency keys without installing nanoid.

Base32 encode or decode. Use when agents must interchange codes for TOTP seeds, IDs, or transport-safe blobs. Returns

CRC32 checksum of text. Call for quick integrity fingerprints on configs, prompts, or cached blobs. Returns hex CRC32

American Soundex codes. Use for fuzzy name matching, de-dupe heuristics, or genealogy-style search keys. Returns the S

Caesar shift cipher. Handy for puzzle agents, CTF helpers, or reversible toy encoding—not for secrets. Returns shifted

Top word frequencies. Call when ranking terms for tags, search hints, or simple content signals. Returns top words by

Unique words with counts. Use for lightweight keyword inventory from notes, pages, or chat transcripts. Returns unique

Redact emails in text. Call before publishing logs, support dumps, or RAG snippets that may contain addresses. Returns

Mask sensitive middle characters. Use before logging secrets, account numbers, or tokens that must stay partially hidd

Repeat a string N times. Handy for fixtures, separators, or test payloads without local loops. Returns the repeated st

Pad a string to width. Use for fixed-width logs, CSV alignment, or receipt fields that need left/right padding. Return

Extract numbers from free text. Call when scraping prices, IDs, quantities, or scores out of messy agent-collected tex

Remove punctuation from text. Useful before tokenization, keyword extraction, or fuzzy match prep. Returns cleaned tex

Strip diacritics from text. Use when normalizing names, search keys, or filenames that must stay ASCII-safe. Returns a

Derive initials from a name for $0.001 USDC. Use this when an agent needs initials inside a workflow without installin

Hard-wrap text to a column width for $0.001 USDC. Use this when an agent needs wrap text inside a workflow without ins

Reverse a string for $0.001 USDC. Use this when an agent needs reverse string inside a workflow without installing a l

Look up supported blockchain network metadata and chain IDs for $0.001 USDC. Static first-party registry only—no live

Search bounded Wikidata entity metadata for $0.001 USDC. Returns stable IDs, labels, descriptions and source links for

Search bounded English Wikipedia metadata for $0.001 USDC through the public Wikimedia API. Returns attributed page li

One-call chain state snapshot: chain id, latest block number, and current gas price (wei + gwei) for Ethereum, Base, P

The latest block number on Ethereum, Base, Polygon, Arbitrum, or Optimism. The cheapest possible on-chain read - the h

Verify an Ed25519 execution certificate against the exact SQL statement you are about to run - the gate your database

Top DeFi protocols ranked by total value locked (TVL) — name, category, chains, 1d/7d TVL change, and mcap/TVL ratio a

Notarize AI output: a signed Ed25519 attestation of the model response plus sha256 content hash, receipt token, and Me

Latest European Central Bank reference exchange rates, normalized JSON. Query: ?base=EUR&symbols=USD,GBP,JPY (symbols

Discovery endpoint listing all 17 available structured-data extractors and the domains each one supports, so an agent

Current Base mainnet gas price (wei/gwei), EIP-1559 base_fee_gwei/priority_fee_gwei, and gas_price_usd.

Hourly weather forecast for any point on Earth from Open-Meteo (blend of ECMWF/GFS/ICON models, refreshed hourly; data

Attested Hedera network facts: HBAR exchange rate, gas fees, supply, node roster, throughput, topic state. Each respon

Deterministic citation formatter — APA 7, MLA 9, Chicago 17 author-date, BibTeX. From structured fields, returns the r

UK DVLA vehicle details by registration plate.

Validate a Dutch identifier (BSN, IBAN or kenteken) offline. Send the identifier in a JSON request body via POST. Paym

Cross-venue funding spreads: Hyperliquid vs Bitget funding rate differences and suggested legs. Use for funding-spread

Hyperliquid funding rate extremes: live perpetual funding APR outliers and which side collects. Use for funding-rate a

Polymarket odds search: prediction market questions and outcome prices for a query. Use when an agent needs prediction

Token price lookup: USD price, market cap, and volume by CoinGecko id or Base ERC20 contract address. Use for spot tok

Live wallet balance on Base: native ETH, USDC ERC20 balanceOf, and transaction nonce. Optional Ethereum mainnet balanc

Crypto news brief for agents: ranked headlines with source URLs and heuristic sentiment. Topics: crypto, base, defi. F

Attested Hedera network facts: HBAR exchange rate, gas fees, supply, node roster, throughput, topic state. Each respon

Attested Hedera network facts: HBAR exchange rate, gas fees, supply, node roster, throughput, topic state. Each respon