RedBison

Render text as a FIGlet ASCII art banner in one of 7 bundled fonts (Standard, Slant, Small, Big, Doom, ANSI Shadow, Mini), optionally wrapped at a column width and inside code comment markers. Printable ASCII only. The page at redbison.dev/ascii-art-text-generator has more fonts. Returns: Text: the banner (show it in a monospace code block). structuredContent { art, font, lines, columns, unsupported[] }. Example input: {"text":"Hello","font":"Slant","layout":"default","width":80,"comment":"none"}

Compute or validate the GS1 mod-10 check digit of an EAN-8, UPC-A, EAN-13 or ITF-14 (GTIN-8/12/13/14) number. Give the digits without the check digit to compute it, or the full code to validate it. Returns: JSON { digits, checkDigit, fullCode, valid, gtin14, formats[] }. valid is true/false when a full code was checked and null when the check digit was computed. Example input: {"code":"400638133393","mode":"compute"}

Base64-decode a string back to UTF-8. Returns: UTF-8 decoded plain text. Example input: {"text":"aGVsbG8gd29ybGQ="}

Base64-encode a UTF-8 string. Returns: Base64-encoded string (UTF-8 safe). Example input: {"text":"hello world"}

Hash a password with bcrypt. Returns: Bcrypt hash string (includes cost + salt). Example input: {"password":"s3cret!","cost":10} On error, includes hint: `cost` must be an integer between 4 and 12. Higher cost is exponentially slower.

Check whether a password matches a bcrypt hash. Returns: JSON { match: boolean }. Example input: {"password":"s3cret!","hash":"$2a$10$abcdefghijklmnopqrstuv"} On error, includes hint: `hash` must be a full bcrypt string starting with $2a$, $2b$, or $2y$.

Calculate Body Mass Index in metric (kg/cm) or imperial (lb/in) units. Returns: JSON { bmi, category } (Underweight / Normal / Overweight / Obese). Example input: {"weight":70,"height":175,"units":"metric"}

Convert text between upper, lower, title, camel, pascal, snake, and kebab case. Returns: String converted to the requested case. Example input: {"text":"hello world example","style":"camel"} On error, includes hint: `style` must be one of: upper, lower, title, camel, pascal, snake, kebab.

Convert Unix permissions between octal (755, 4755), symbolic (rwxr-xr-x) and ls -l strings, or apply a chmod expression such as 'go-w,u+x' to a starting mode. Explains each class, setuid/setgid/sticky bits and risky modes, and gives umask defaults. Returns: JSON { octal, symbolic, ls, description[], warnings[], command, symbolicArg, umaskDefaults{ umask, newFile, newDirectory } }. Example input: {"mode":"rwxr-x---"} On error, includes hint: Use 1-4 octal digits, nine rwx characters (optionally with a leading file type), or a symbolic expression like u+x,go-w.

Convert a color between hex, rgb, and hsl. Accepts inputs like '#3B82F6', 'rgb(59,130,246)', or 'hsl(217,91%,60%)'. Returns: JSON with hex, rgb, and hsl representations of the color. Example input: {"color":"#3b82f6"} On error, includes hint: `color` accepts #rgb, #rrggbb, rgb(r,g,b), or hsl(h,s%,l%).

Build a harmonious color palette from one base color (complementary, analogous, triadic, split-complementary, tetradic, square, monochromatic or tints and shades). Returns each color as HEX, RGB, HSL and OKLCH with WCAG contrast against white and black, an 11-step 50-950 scale of the base, and ready-to-paste CSS variables and Tailwind config. Same maths as https://redbison.dev/color-palette-generator. Returns: JSON { base, rule, wheel, colors[] { role, hex, rgb, hsl, oklch, contrastOnWhite, contrastOnBlack, bestTextColor, wcagNormalText }, scale { '50'..'950': hex }, baseScaleStep, css, tailwindV3, tailwindV4 }. Example input: {"base":"#3b82f6","rule":"triadic","wheel":"rgb","name":"brand"} On error, includes hint: Pass the base color as hex like #3b82f6 (rgb(), hsl(), oklch() and CSS names also work). rule must be one of complementary, analogous, triadic, split-complementary, tetradic, square, monochromatic, shades.

Split a delimited string into one item per line. Returns: Multi-line string, one item per line. Example input: {"text":"apple, banana, cherry","separator":",","trim":true}

Compute compound interest: A = P(1 + r/n)^(nt). Returns: JSON { interest, total } computed as P(1+r/n)^(nt). Example input: {"principal":10000,"annualRatePercent":5,"years":10,"compoundsPerYear":12}

Compute the WCAG contrast ratio between two hex colors and report AA/AAA pass/fail for normal and large text. Returns: JSON { ratio, AA, AAA, AALarge, AAALarge } for the two colors. Example input: {"foreground":"#ffffff","background":"#3b82f6"} On error, includes hint: Both colors must be hex (#rgb or #rrggbb).

Build a standard five-field cron expression from plain choices (every N minutes, hourly, daily, weekly, monthly, yearly) or explain an existing one. Returns the expression, an English description, the next run times in a time zone, and the same schedule for crontab, Kubernetes, GitHub Actions, Quartz and AWS EventBridge. Returns: JSON { expression, description, nextRuns[], timezone, platforms[{ id, name, value, notes[] }], warnings[] }. value is null on Quartz/EventBridge when both day fields are restricted. Example input: {"frequency":"weekly","daysOfWeek":["mon","wed","fri"],"hours":[9],"minute":30,"timezone":"America/New_York"} On error, includes hint: Give either plain choices (frequency plus minute/hours/days) or a five-field expression. Days of week accept names or 0-6 with 0 = Sunday.

Validate a standard 5-field cron expression (minute hour day month weekday). Returns a human-readable summary and any parse error. Returns: JSON { valid: boolean, nextRuns?: string[], error?: string }. Example input: {"expression":"*/5 * * * *"} On error, includes hint: `expression` must be a 5-field cron (minute hour dom month dow). 6-field / Quartz syntax is not supported.

Pretty-print or minify CSS, SCSS or Less, optionally sorting declarations alphabetically. Sorting is cascade-safe: a shorthand and its longhands (border / border-top, margin / margin-top, font / line-height) keep their original relative order. Minify removes comments and whitespace only; values such as 0px or colours are never rewritten. Returns: Text: the stylesheet. structuredContent { code, movedDeclarations, warnings[] }. Example input: {"css":".a{z-index:1;color:red;border-top:1px solid;border:0}","mode":"beautify","syntax":"css","sort":true,"indent":2} On error, includes hint: Unbalanced braces or an unterminated string or comment are reported as errors.

Build a CSS linear or radial gradient string from color stops. Returns: CSS gradient string (linear or radial). Example input: {"type":"linear","angle":45,"stops":["#3b82f6","#8b5cf6"]} On error, includes hint: `type` is 'linear' or 'radial'; provide at least 2 color `stops`.

Parse CSV text into JSON. Uses the first row as headers unless header=false. Returns: JSON array of row objects keyed by the header row. Example input: {"text":"name,age\nAda,36\nGrace,85","delimiter":","} On error, includes hint: `text` must be CSV with a header row unless `header:false`. Escape embedded quotes as "".

Convert a curl command (bash/zsh quoting, $'...' strings, \ line continuations, or Windows cmd ^ escaping from 'Copy as cURL') into JavaScript fetch, Node Axios, Python requests, Go net/http or PHP ext-curl. Follows curl semantics: -d implies POST with application/x-www-form-urlencoded, repeated -d joins with &, --json sets JSON headers, -G moves data to the query string, -F is multipart, -u is Basic auth, no redirects without -L. Nothing is sent over the network. Returns: Text: the generated code, followed by notes on anything not translated. structuredContent { code, method, url, headers[{ name, value }], hasBody, warnings[] }. Example input: {"command":"curl -X POST https://api.example.com/v1/items -H 'Content-Type: application/json' -d '{\"name\":\"Ada\"}'","target":"python"} On error, includes hint: Send the command exactly as copied, including quotes. The word curl must be present.

Compute the difference between two ISO 8601 timestamps in days, hours, minutes, and seconds. Returns: JSON with milliseconds, totalSeconds/Minutes/Hours/Days, and a { days, hours, minutes, seconds } breakdown. Example input: {"from":"2026-01-01T00:00:00Z","to":"2026-07-11T12:00:00Z"} On error, includes hint: Both `from` and `to` must be ISO 8601 timestamps.

Convert one or more 'docker run' commands into a Compose file (services, ports, volumes, environment, networks, healthcheck, GPUs, limits), or convert a compose.yaml back into docker run commands. Unsupported flags are reported as warnings. Returns: run_to_compose: JSON { compose (YAML text), services[], warnings[] }. compose_to_run: JSON { commands[], warnings[] }. Example input: {"input":"docker run -d --name web -p 8080:80 -v html:/usr/share/nginx/html --restart unless-stopped nginx:alpine"} On error, includes hint: Each command must start with 'docker run' (or 'docker container run'). Separate several commands with new lines.

Compute the equated monthly installment (EMI) for a loan. Returns: JSON { emi, totalInterest, totalPayment } for the loan. Example input: {"principal":500000,"annualRatePercent":8.5,"months":240}

Convert between Unix epoch seconds/milliseconds and ISO 8601. Pass a number to convert to ISO, or an ISO string to convert to epoch. Returns: JSON with ISO string, epoch seconds, epoch milliseconds, and a UTC-formatted representation. Example input: {"value":"1700000000"} On error, includes hint: `value` is a string: either an integer (seconds or ms since epoch) or an ISO 8601 timestamp.

Escape or unescape a string for JSON, HTML, XML, JavaScript, or SQL. Returns: Escaped or unescaped string for the chosen format. Example input: {"text":"He said \"hi\"","format":"json","mode":"escape"} On error, includes hint: `mode` is 'escape' or 'unescape'; `format` is one of: json, html, xml, js, sql.

Return lines that appear more than once in the input, with their occurrence counts. Returns: JSON array of { value, count } for lines appearing more than once. Example input: {"text":"apple\nbanana\napple\ncherry\nbanana"}

Get full metadata for a specific RedBison tool by its id (slug). Returns: Full JSON metadata for the tool: { id, name, description, url, category, subcategory?, keywords[] }. Example input: {"id":"jwt-decoder"}

Combine .gitignore templates (based on github/gitignore) for languages, frameworks, tools, editors and operating systems into one deduplicated file, optionally test paths against it. Template ids: node, python, django, jupyter, java, maven, gradle, kotlin, android, go, rust, ruby, rails, php, laravel, dotnet, c, cpp, swift, flutter, elixir, scala, r, nextjs, terraform, unity, docker, secrets, vscode, jetbrains, visualstudio, eclipse, vim, emacs, sublime, macos, windows, linux. Returns: JSON { content (.gitignore text), unknownTemplates[], duplicatesRemoved, tests[{ path, ignored, rule{pattern,line,negate}, via }] }. Example input: {"templates":["node","macos","vscode"],"testPaths":[".env","node_modules/x.js",".vscode/settings.json"]}

Compute a cryptographic hash of a string. Returns: Hex digest of the input using the requested algorithm. Example input: {"text":"hello world","algorithm":"sha256"} On error, includes hint: `algorithm` must be one of: md5, sha1, sha256, sha384, sha512.

Hash two inputs with the same algorithm and compare them in constant time. Useful for verifying file integrity. Returns: JSON { match: boolean } computed with a constant-time comparison. Example input: {"a":"hello","b":"hello","algorithm":"sha256"} On error, includes hint: `algorithm` (optional, default sha256) must be one of: md5, sha1, sha256, sha384, sha512.

Return server status, name, version, and uptime info. Use this to monitor the MCP server. Returns: JSON { status, name, version, startedAt, timestamp }. Example input: {}

Explain how to use any RedBison MCP tool, with its input schema, a sample input and the sample output it produces. Call with no arguments for the list of tools; pass `tool` for one tool, and `calculator` with tool 'run_calculator' for one calculator. Returns: JSON with a tool's { usage, returns, inputSchema, sampleInput, sampleOutput }, or the list of tools when called with no arguments. Example input: {"tool":"list_calculators"}

Compute an HMAC (RFC 2104) with SHA-256, SHA-1, SHA-384 or SHA-512 and return it in hex, Base64 and Base64url. Optionally build a GitHub, Stripe or Slack webhook signature, and check an expected signature with a constant-time comparison. Returns: JSON { algorithm, hex, base64, base64url, bits, key_bytes, message_bytes, signed_string, header, match } where match is null unless `expected` was given. Example input: {"message":"The quick brown fox jumps over the lazy dog","key":"key","algorithm":"SHA-256"} On error, includes hint: `algorithm` is SHA-256, SHA-1, SHA-384 or SHA-512; `key_encoding` and `message_encoding` are utf8, hex or base64; `preset` is plain, github, stripe or slack.

Pretty-print an HTML fragment. Returns: Pretty-printed HTML string with normalized indentation. Example input: {"html":"<div><p>hi</p><p>there</p></div>","indent":2}

Look up HTTP status codes: meaning, defining RFC section (RFC 9110 and others from the IANA registry), when to send it and common pitfalls. Pass a code (404), a class (5xx) or words (rate limit). Unofficial nginx and Cloudflare codes are included and flagged. Returns: JSON { query, count, results[] } where each result has { code, name, class, spec, official, deprecated, cacheableByDefault, summary, usage, note }, plus unknownCode text when a 3-digit code is not registered. Example input: {"query":"429"}

Convert an IPv4 address between dotted-decimal, integer, binary, and hex forms. Accepts any of those as input. Returns: JSON { decimal, integer, hex, binary } representations of the IPv4 address. Example input: {"value":"192.168.1.1"} On error, includes hint: `value` accepts dotted (192.168.0.1), integer (3232235521), 32-bit binary, or 0x-prefixed hex.

Format JavaScript, TypeScript or JSX with js-beautify, or minify JavaScript/TypeScript by removing comments and whitespace (no renaming, no rewriting; line breaks are kept where automatic semicolon insertion needs them). The output is re-lexed and compared token by token with the input. Returns: Text: the formatted or minified code. structuredContent { code, mode, inputBytes, outputBytes, savedPercent, warnings[] }. Example input: {"code":"function add(a,b){return a+b}","mode":"beautify","language":"javascript","indent":2,"brace_style":"collapse","keep_license":true} On error, includes hint: Pass the whole file as `code`. An unterminated string, comment or regex is reported with its line and column.

Pretty-print a JSON string with a chosen indent size. Returns: Pretty-printed JSON string with the requested indent, or an error message if the input is invalid. Example input: {"text":"{\"a\":1,\"b\":[2,3]}","indent":2} On error, includes hint: Pass valid JSON as `text` (double-quoted keys/strings, no trailing commas). `indent` is an integer between 0 and 10.

Validate a JSON document against a JSON Schema (drafts 06, 07, 2019-09 and 2020-12, via Ajv, all errors reported with JSON Pointer paths and formats such as date-time, email, uuid, ipv4/ipv6 checked), or infer a starter schema from sample JSON. Leave `schema` empty to infer. Returns: Validate: text summary plus structuredContent { mode, valid, draft, errors[{ path, message, keyword, schemaPath, params }], warnings[] }. Infer: the schema as JSON text and structuredContent { mode, schema }. Example input: {"data":"{\"name\":\"Ada\",\"age\":-1}","schema":"{\"type\":\"object\",\"properties\":{\"age\":{\"type\":\"integer\",\"minimum\":0}},\"required\":[\"name\",\"email\"]}","draft":"auto"} On error, includes hint: Both `data` and `schema` are JSON text, not objects. Send an empty `schema` to generate one from `data`.

Convert an array of JSON objects to CSV. Columns are inferred from the union of keys. Returns: CSV string with a header row derived from the first object's keys. Example input: {"json":"[{\"name\":\"Ada\",\"age\":36},{\"name\":\"Grace\",\"age\":85}]","delimiter":","} On error, includes hint: `json` must be a JSON-encoded array of objects (parameter name is `json`, not `text`).

Convert a JSON string to YAML. Returns: YAML representation of the parsed JSON value. Example input: {"json":"{\"name\":\"Ada\",\"skills\":[\"math\",\"logic\"]}"} On error, includes hint: Pass the JSON as `json` (a stringified JSON value), not as a JS object.

Validate a JSON string. Returns { valid, error? }. Returns: JSON { valid: boolean, error?: string }. Example input: {"text":"{\"a\":1}"} On error, includes hint: Pass the JSON string as `text`.

Decode a JWT and return its header + payload. Does NOT verify the signature. Returns: JSON with decoded { header, payload, signature } sections of the JWT. Example input: {"token":"eyJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjMifQ.abc"} On error, includes hint: `token` must be a compact JWT with three base64url-encoded parts separated by dots.

Join lines with a separator (comma by default). Empty lines are skipped. Returns: Single-line string with items joined by the chosen separator. Example input: {"text":"apple\nbanana\ncherry","separator":", ","quote":false}

List the calculators that run_calculator can execute (finance, health, maths, statistics, construction, science, everyday and engineering), with each one's inputs, units, defaults and an example. Filter with an optional search query. Returns: JSON { total, calculators[] } where each has { id, title, summary, url, inputs (JSON Schema per field), example }. Example input: {"query":"mortgage","limit":5}

List all tool categories and subcategories available on RedBison. Returns: JSON array of { category, count } entries covering the full RedBison catalog. Example input: {}

Compare two newline-separated lists. Returns union, intersection, only-in-A, and only-in-B. Returns: JSON { union, intersection, onlyInA, onlyInB } arrays. Example input: {"a":"apple\nbanana\ncherry","b":"banana\ncherry\ndate"}

Generate placeholder lorem ipsum text. Returns: Lorem ipsum text of the requested size. Example input: {"unit":"paragraphs","count":2}

Turn CSV, TSV (spreadsheet paste) or an existing Markdown table into a GitHub Flavored Markdown table. The first row is the header; pipes are escaped as \|, line breaks inside cells become <br>, and columns can be padded so the pipes line up (CJK-width aware). Returns: Text: the Markdown table. structuredContent { markdown, rows (including header), columns, detected ('csv' | 'tsv' | 'markdown' | 'other'), errors[] }. Example input: {"text":"Item,Qty,Price\nApple,3,$1.20\nKiwi,12,$0.50","align":"none","pretty":true,"outer_pipes":true,"bold_header":false} On error, includes hint: Put the header in the first row. Quote CSV fields that contain commas or line breaks.

Find the MIME (media) type for a file extension or file name, or the extensions for a MIME type. Returns the type, whether it is IANA-registered, aliases, notes and the Content-Type header to send. Returns: JSON { query, matchedBy: 'extension'|'mime'|'text', count, results[] } with { mime, extensions[], name, category, registered, aliases[], spec, note, contentType }. Example input: {"query":"woff2"}