Cold Email — Writes a short, honest first outreach message to a stranger in business, in the recipient's language, with a subject line, one specific reason for writing and one small ask. Use when asked to write a cold email, a first outreach message, a sales or partnership introduction, or a prospecting note, in any language. One-time purchase of the SKILL.md file itself (Agent Skills format), not an API call: $0.03 USDC, yours forever incl. free re-downloads and new versions. Tested with a str…

Monthly US federal receipts, outlays and deficit (or surplus), plus the trailing 12-month deficit, from the Monthly Treasury Statement. US Treasury, public domain.

Decode a JWT and verify its signature with the public keys of a JWKS URL (RS256, ES256, EdDSA...) or an HMAC secret, checking expiry, audience and issuer; returns header, claims and the exact reason if invalid. Tokens are not stored.

Dominant colors of an image (URL or base64) with their share, in HEX and RGB, plus the average color and light/dark tone. For brand palettes, themes or tagging images by color.

Convert integers of any size (signed) between bases 2 to 36: binary, octal, decimal, hex, base32, base36, with bit and byte length and two's complement. Accepts 0x/0b/0o prefixes.

npm package profile: latest version, description, license, repository, dependencies, unpacked size, weekly and monthly downloads, maintainers and deprecation flag. For dependency choice and audits.

Find a company's LEI (Legal Entity Identifier) by name, or the record of a LEI: legal name, country, legal form, address, entity and registration status, renewal date, direct parent and company register number.

US dollar reference rates from the Federal Reserve Bank of New York: effective fed funds rate (EFFR) with the Fed's target range, SOFR with 30/90/180-day averages, OBFR, TGCR and BGCR, with volumes and percentiles.

Write a number or money amount in words, in Spanish or English (EUR, USD, GBP, MXN), with correct Spanish apocope (veintiún, un millón de euros). For invoices, cheques and contracts.

Count the tokens of a text with OpenAI tokenizers (o200k for GPT-4o/4.1/5, cl100k for GPT-4/3.5) plus estimates for Claude, Llama and Gemini, with characters per token. Budget LLM calls and split contexts.

Validate JSON (with line and column of the error), pretty-print or minify it, describe its structure (depth, keys, value types) and extract a value by path such as data.items[0].price.

Search biomedical literature indexed in PubMed, via OpenAlex (CC0): title, authors, journal, date, DOI, PMID, citation count and open-access link, newest first, with optional year filter. Metadata only (no abstracts).

Trade result: gross and net profit or loss after entry/exit fees and funding, return on margin, price change, break-even price and notional. Long or short, with leverage.

Validate and normalize a phone number from any country: E.164, national and international format, type (mobile, landline, toll-free, VoIP...), country, region, original carrier and time zones. Nothing is called or stored.

Keyless public RPC endpoints (HTTPS and WebSocket) of any EVM chain by name or chainId, with block explorers, native currency and website. Lets an agent connect to any chain.

All links on a page classified as internal or external, with anchor text, nofollow/sponsored, new-tab flags and the most linked external domains. For SEO, crawling and audits.

Redact personal data from text without AI: emails, phone numbers, IBANs, card numbers (Luhn-checked), Spanish DNI/NIE, IPs, crypto addresses and URLs, replaced by labels ([EMAIL_1]) or asterisks. Before sending text to an LLM or sharing logs. Text is not stored.

Estimate password strength with Dropbox's zxcvbn: score 0-4, estimated guesses and crack time for online and offline attacks, weak patterns found (dictionary, dates, sequences...) and tips. Evaluated in memory, never stored or logged.

Python package profile from PyPI: latest version and date, summary, license, required Python, links, dependencies, number of versions and yanked flag.

Generate a QR code as SVG or PNG (base64 and data URI) for any text, URL, payment link, Wi-Fi or vCard, with error-correction level, scale and colors.