https://vibeengines.com/topic/developer-utilities The fast, offline, no-sign-up utilities you reach for daily — decode a JWT, plan a subnet, convert an epoch, generate an ID. Everything runs in your browser; nothing is sent anywhere. en Sat, 01 Aug 2026 00:00:00 GMT https://vibeengines.com/tools/scoping-question-log https://vibeengines.com/tools/scoping-question-log Tool A drill for the skill every discovery call actually tests. Two underspecified customer asks, twelve candidate questions each, and a budget of six — spend them, see what the customer really says, and get each question scored on whether the answer changes what you build. Ends with a copyable scoping doc, a coverage map across the six axes, and the thing that was really going on that you either found or missed. Sat, 01 Aug 2026 00:00:00 GMT https://vibeengines.com/tools/exponential-backoff-calculator https://vibeengines.com/tools/exponential-backoff-calculator Tool An interactive exponential-backoff calculator. Set the base delay, multiplier, cap and retry count, then see the exact delay before every retry attempt, the worst-case total wait, and how full and equal jitter change the numbers — so you can size retries that recover fast without hammering a service that is already struggling. Tue, 28 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/cosine-similarity-calculator https://vibeengines.com/tools/cosine-similarity-calculator Tool An interactive cosine-similarity and vector-distance calculator. Paste two vectors and instantly see their dot product, magnitudes, cosine similarity, cosine distance, the angle between them, and Euclidean and Manhattan distance — the exact numbers behind how embedding search decides which items are “close.” See why cosine ignores magnitude and when to prefer it over Euclidean distance. Tue, 28 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/llm-sampling-simulator https://vibeengines.com/tools/llm-sampling-simulator Tool An interactive LLM sampling playground. Adjust temperature, top-p (nucleus) and top-k and watch the next-token probability distribution reshape in real time — from sharp and near-greedy at low temperature to flat and creative at high temperature, with the long tail trimmed by top-p and top-k. The exact softmax math that turns raw logits into the choices a language model actually samples from. Tue, 28 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/skill-linter https://vibeengines.com/tools/skill-linter Tool A client-side linter for agent skill files (SKILL.md). Paste your skill and it scores the structure a good skill needs — a clear name and description, an explicit “when to use” trigger, concrete examples, imperative step-by-step instructions, and a scoped length — against a 12-point rubric, with per-criterion feedback on what is missing. Everything runs in your browser; nothing is uploaded. Built to catch the quality gaps that separate a curated skill from the average public one. Sun, 26 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/jwt-decoder https://vibeengines.com/tools/jwt-decoder Tool A client-side JWT decoder. Paste a JSON Web Token and instantly see the decoded header and payload, with the standard claims (iss, sub, aud, exp, iat, nbf) explained and the expiry shown as a live countdown. Everything runs in your browser — the token is never sent anywhere, so it is safe to paste a real one. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/cidr-calculator https://vibeengines.com/tools/cidr-calculator Tool An IPv4 subnet calculator. Enter a CIDR block like 10.0.0.0/24 and instantly see the network address, broadcast address, usable host range, total and usable host counts, the subnet mask and wildcard mask, and the binary breakdown. Handy for planning VPC subnets, firewall rules and route tables — all computed in your browser. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/unix-time-converter https://vibeengines.com/tools/unix-time-converter Tool A Unix timestamp converter. Paste an epoch value (seconds or milliseconds — auto-detected) to get the human-readable date in both UTC and your local timezone, or pick a date to get the timestamp back. Shows the ISO 8601 string, relative time, and the current epoch ticking live. Runs entirely in your browser. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/uuid-ulid-generator https://vibeengines.com/tools/uuid-ulid-generator Tool A UUID and ULID generator. Produce cryptographically-random version-4 UUIDs or sortable ULIDs, one at a time or in bulk, with one-click copy. Explains when to reach for a random UUID versus a time-sortable ULID, and shows the structure of each. Uses the browser’s secure crypto — nothing is generated on or sent to a server. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/regex-tester https://vibeengines.com/tools/regex-tester Tool An interactive regular-expression tester. Type a pattern and flags, paste your test text, and see all matches highlighted with their positions, plus every numbered and named capture group. Explains the flags and common tokens, and runs entirely in your browser so nothing is sent anywhere. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/base64-url-tools https://vibeengines.com/tools/base64-url-tools Tool A Base64 and URL encoding tool. Paste text to get its standard Base64, URL-safe Base64URL, and percent-encoded forms at once, or switch to decode to recover the original — all UTF-8 aware and computed in your browser. Handy for JWTs, data URIs, query strings and API debugging. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/chmod-calculator https://vibeengines.com/tools/chmod-calculator Tool A Unix file-permission calculator. Toggle read, write and execute for owner, group and others to get the octal mode (like 755) and the symbolic string (rwxr-xr-x), or type an octal number to see exactly which permissions it grants. Explains what each bit means and the common modes to reach for. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/password-entropy https://vibeengines.com/tools/password-entropy Tool A password strength calculator based on entropy. Type a password (analyzed only in your browser) to see the character pool it draws from, its entropy in bits, a strength rating, and an estimated time to crack at realistic offline attack speeds. Explains why length beats complexity and where the entropy model’s limits are. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/cron-builder https://vibeengines.com/tools/cron-builder Tool A cron expression builder and decoder. Type a five-field cron schedule and instantly get a plain-English description plus the next several times it would fire, or start from a common preset. Supports ranges, lists and step values, and explains what each of the five fields means — all computed in your browser. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/sql-formatter https://vibeengines.com/tools/sql-formatter Tool A lightweight SQL formatter. Paste a cramped, one-line query and get it back with each major clause on its own line, keywords cased consistently, and conditions indented — so you can actually read and review it. Runs in your browser; it formats for readability rather than parsing the full SQL grammar. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/md-table-generator https://vibeengines.com/tools/md-table-generator Tool A Markdown table generator. Paste comma- or tab-separated data and get a properly aligned Markdown table you can drop into a README, a pull request, or docs — with a live rendered preview and a choice of column alignment. Everything runs in your browser. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/diff-checker https://vibeengines.com/tools/diff-checker Tool A text diff checker. Paste an original and a changed version to see a line-by-line comparison — additions, removals and unchanged lines highlighted — computed with a longest-common-subsequence diff, entirely in your browser. Handy for comparing configs, logs, JSON, or any two versions of text. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/tools/json-format-diff https://vibeengines.com/tools/json-format-diff Tool A JSON formatter, validator and diff tool. Paste JSON to validate it and pretty-print it, with clear error messages on invalid input. Paste a second document to see a key-sorted, value-level diff — so real changes stand out instead of formatting or key-order noise. Everything runs in your browser. Fri, 24 Jul 2026 00:00:00 GMT https://vibeengines.com/handbook/oauth-auth-deep https://vibeengines.com/handbook/oauth-auth-deep Handbook How "Sign in with Google" lets an app act for you without ever seeing your password. OAuth swaps your credentials for a scoped, revocable token, delivered via a short-lived authorization code that's worthless on its own — turning it into a token needs a back-channel exchange the browser can't make. Two parameters guard the flow: state (a random value echoed back, blocking forged/CSRF responses) and PKCE (challenge = SHA-256(verifier), so a stolen code can't be redeemed without the secret). Plus authentication vs authorization, OIDC/ID tokens, and the traps (implicit flow, unvalidated tokens, wide scopes, token leaks). With worked math and runnable code. Mon, 20 Jul 2026 00:00:00 GMT