Search the string-transformation utilities this server can run (247 total, across categories like Encoding, Hashing, Ciphers, Compression, Data Formats, Analysis, Generators and more). Returns {items: [{id, name, category, description}], total, categories}, best matches first. Use this first to find an id, then call describe_utility for its exact parameters before run_utility. category and query combine (a utility must match both); omit both to browse the whole catalog. A category that does not exist matches nothing rather than failing, so take one from categories. There is no paging: when total exceeds the items returned, raise limit or narrow the query. Reads the bundled catalog only: no network access and no rate limit.

Full documentation for one utility: its parameters (kind, default, options/bounds, description), the value types it accepts/produces, tags, aliases, worked examples (input, inputEncoding, params and expected output — byte outputs there use the app's display format, while run_utility returns bytes as base64), and which runtime capabilities it needs. Call this before run_utility to learn the exact parameter names and defaults; skip it for a utility you have already described. id must be an exact, case-sensitive utility id: names and aliases are not resolved, so look those up with list_utilities first. An unknown id returns isError ("unknown utility: "). When unavailable is set, run_utility and run_pipeline refuse the utility.

Run a single utility on input and return {output, outputEncoding?}. For two or more transformations in a row, make one run_pipeline call instead of chaining run_utility calls; if you do not know the id yet, find it with list_utilities. Plain text output is returned as-is; a JSON-producing utility returns pretty-printed JSON text; a byte-producing utility (e.g. gzip_compress, get_bytes) returns base64 with outputEncoding: "base64". inputEncoding controls how input itself is decoded first: "text" (default) uses it as-is, "base64" or "hex" decode it to raw bytes, "json" parses it. Params are validated against describe_utility's spec; invalid ones are rejected. Input is capped at 1,000,000 bytes, output text past 1,000,000 characters is cut off (flagged truncated, with fullLength), and the call is stopped after 20s. A failing utility returns isError with the error message. Utilities that run arbitrary user JavaScript (e.g. "custom_js") are refused, and the few that need a browser DOM parser (e.g. "xml_to_json", "html_table_to_csv") fail here.

Run several transformations on input in one call: an ordered list of steps (string-utility-belt v3 schema), each step's output feeding the next. Besides utility steps, a pipeline can hold branches (parallel forks merged back together), macros (named sub-pipelines) and "run on each" steps (a sub-pipeline run on every line, delimited piece, JSON array element or JSON object value). Prefer this to chaining run_utility calls; for a single transformation, run_utility is simpler. Returns {output, outputEncoding?, errors, timings, skipped, halted}: errors maps step id to its error message, timings maps step id to milliseconds. Provide exactly one of steps or share (a #/p/<payload> share link, a full URL containing one, or the bare payload). Untrusted step data is sanitized first, so malformed entries are dropped rather than rejected. Refused outright: pipelines with more than 100 steps (nested steps counted), unknown utility ids, enabled steps with invalid params, and any step that would run arbitrary user JavaScript (e.g. "custom_js") — LLM-driven code execution is out of scope. Input is capped at 1,000,000 bytes, output text past 1,000,000 characters is cut off (flagged truncated, with fullLength), and the call is stopped after 20s.

Guess what input is — JSON, YAML, TOML, XML, HTML, CSV/TSV, base64/base32/hex, URL-encoding, JWT, UUID, data URI, gzip/zlib, email, URL, IP address, unix timestamp, Markdown, SQL, Morse code, ROT13, plain binary — and return {candidates: [{format, confidence, note}]}, best first, confidence 0-1. Use it when you are handed an opaque or unlabelled value and must pick a utility for it; skip it when the format is already known. It only identifies, never transforms: to decode, search list_utilities for the top format (base64 -> base64_decode, JWT -> jwt_decode) and run that with run_utility. Ambiguous input yields several candidates (all-digit text can be a timestamp, JSON and hex at once); treat anything below about 0.45 as a weak guess. Use inputEncoding "base64"/"hex" only to deliver binary data such as gzip bytes: it is decoded before detection, so a base64 string you want identified must stay "text" (the default). Empty input yields an empty list.