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Developer & agent tools

Tools and APIs for builders shipping with AI.

247 browser-native tools and REST APIs for developers and the agents they build. No signup, no keys — run the computation in a tab or call the endpoint.

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247
Browser-native tools
68
Dedicated REST APIs

Spotlight

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Regex Tester

Regex

Test patterns with match extraction and ReDoS protection.

Test and debug regular expressions with live matching, capture group extraction, plain-English explanations, and ReDoS vulnerability detection. Supports JavaScript, Python, and Go regex flavors.

✅

Agent Skill Validator

New

Cross-framework skill linting for AI agents.

Validate skill definitions across OpenClaw, Claude, Codex, and MCP with portability scoring and exact fixes

?!

Format Detective

Detect

Identify data formats and convert between JSON, YAML, XML, CSV.

Detect unknown data formats and convert between JSON, YAML, XML, CSV, TOML, and text with browser + API workflows

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API Suite — fast REST endpoints for app and agent workflows

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API + Agent Integrations — REST APIs, OpenAPI, skills bundles, and WebMCP

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All Tools

AI Tools

Agent Skill Validator

Validate skill definitions across OpenClaw, Claude, Codex, and MCP with portability scoring and exact fixes

Open
AI Tools

SkillSpec Converter

Convert one canonical skill definition into OpenClaw SKILL.md, Claude blocks, Codex scaffolds, and MCP manifest snippets

Open
AI Tools

Skill Regression Suite Builder

Build deterministic regression suites for skill updates with risk-weighted pass-rate gates and CI-ready case definitions

Open
AI Tools

Skill Scope Collision Detector

Detect cross-scope skill version and enabled-state collisions across global, user, project, and local configuration layers

Open
AI Tools

Skill Payload Budget Optimizer

Optimize skill pack token and byte budgets against context windows with deterministic compress, defer, and keep recommendations

Open
AI Tools

Tool Approval Matrix Compiler

Compile cross-platform allow, ask, and deny decisions for tool capabilities across Codex, Claude, and managed MCP policies

Open
AI Tools

Skill Release Canary Planner

Generate staged canary rollout plans for skill updates with deterministic stop conditions and rollback checklists

Open
AI Tools

Trace Failure Classifier

Classify failed trace events into root-cause buckets and output deterministic remediation guidance for agent incident triage

Open
Dev Tools

CLI UX Linter

Audit your CLI --help output for discoverability, flag consistency, examples, and error guidance

Open
Dev Tools

AI CLI Generator

Generate Node or Python CLI scaffolds from OpenAPI with auth wiring, retries, pagination, and shell completion stubs

Open
Dev Tools

CSV Endpoint Builder

Turn CSV data into endpoint-ready mock responses, OpenAPI snippets, and production starter templates

Open
AI Tools

LLM Crawl Policy Validator

Validate robots.txt and llms.txt files, detect conflicts, simulate AI bot access, and export corrected policies

Open
AI Tools

MCP Governance Composer

Compose managed MCP governance packs with allow/deny lists, approval boundaries, and operator rollout checklists

Open
AI Tools

MCP Tool Search Budget Simulator

Simulate context-window usage for full MCP tool injection versus search-first retrieval strategies

Open
AI Tools

Claude Settings Scope Diff

Diff managed, user, project, and local settings scopes and compute the effective merged Claude configuration

Open
AI Tools

Claude Hook Policy Simulator

Simulate Claude hook decisions for pre/post tool events and validate policy rule coverage before rollout

Open
Dev Tools

OpenProse Flow Linter

Lint OpenProse flow graphs for unreachable stages, dangling edges, privileged paths, and approval gaps

Open
AI Tools

OpenClaw Skill Trust Scanner

Scan SKILL.md instructions for destructive command patterns, missing safety boundaries, and trust posture

Open
AI Tools

Agent Tool Blast Radius Mapper

Map tool capability blast radius, score operational risk, and produce least-privilege policy buckets

Open
Dev Tools

Trace Context Validator

Validate W3C traceparent and tracestate headers for distributed tracing correctness and propagation safety

Open
Dev Tools

Retry & Idempotency Contract Builder

Generate endpoint-level retry and idempotency contracts with deterministic test vectors and rollout guidance

Open
Dev Tools

CSP & SRI Policy Builder

Build strict CSP header templates and SRI tag snippets for frontend script hardening and safer deployments

Open
AI Tools

AI Model Comparison

Compare AI models: pricing, context windows, benchmarks, and specs side by side

Open
Formatter

JSON Formatter & Validator

Format, validate, and beautify JSON with syntax highlighting

Open
AI Tools

MCP Server Directory

Curated directory of Model Context Protocol servers with install commands and categories

Open
Generator

CSS Flexbox & Grid Playground

Interactive CSS Flexbox and Grid playground with live visual preview and code output

Open
API Dev Tools

Regex Tester

Test and debug regular expressions with live matching, capture group extraction, plain-English explanations, and ReDoS vulnerability detection. Supports JavaScript, Python, and Go regex flavors.

Open
API Generator

QR Code Generator

Generate QR codes for URLs, text, WiFi, and app flows — export SVG/PNG or automate generation via free API

Open
AI Tools

AI Agent Framework Comparison

Compare AI agent frameworks: LangChain, CrewAI, AutoGen, Mastra, and more side by side

Open
Converter

CSS to Tailwind Converter

Convert vanilla CSS to Tailwind CSS utility classes with property mapping and spacing scale conversion

Open
Generator

Password Generator

Generate strong, cryptographically secure passwords with customizable length, character sets, and entropy meter

Open
AI Tools

AI Pricing Calculator

Compare AI API costs across providers for your specific workload

Open
Converter

HTML to JSX Converter

Convert HTML to JSX with automatic attribute renaming, style objects, self-closing tags, and comment conversion

Open
Generator

CSS Box Shadow Generator

Visual CSS box-shadow generator with multiple layers, live preview, presets, and instant CSS copy

Open
API AI Tools

LLM Token Counter

Count tokens and estimate model costs across GPT, Claude, Gemini, Llama, and more — with optional free API access for apps and agents

Open
API Generator

Color Palette Generator

Generate accessible color palettes and convert HEX/RGB/HSL for UI systems, design tokens, and branding workflows

Open
Dev Tools

Mermaid Diagram Viewer

Render Mermaid diagrams instantly — flowcharts, sequence diagrams, and more with SVG/PNG export

Open
Dev Tools

Docker Compose Validator

Validate Docker Compose YAML with structural checks, dependency validation, and common mistake detection

Open
Dev Tools

JWT Decoder & Inspector

Decode and inspect JSON Web Tokens — header, payload, claims, and expiration

Open
AI Tools

CLAUDE.md / Rules File Generator

Generate CLAUDE.md, .cursorrules, and copilot-instructions.md files for your project with templates

Open
Dev Tools

OpenAPI / Swagger Preview

Paste an OpenAPI or Swagger spec and see interactive API documentation instantly

Open
Dev Tools

GitHub Actions YAML Builder

Build GitHub Actions workflows visually — templates for Node, Python, Docker, deployment, and matrix strategies

Open
Converter

Color Converter

Convert colors between HEX, RGB, HSL, HSV, CMYK, and Tailwind CSS with contrast checker

Open
API Dev Tools

Cron Expression Builder

Build and validate cron expressions with human-readable schedule descriptions, next-run previews, and a free REST API for automation workflows.

Open
Generator

SVG Path Editor

Interactive SVG path editor with visual canvas, operations, and command reference

Open
AI Tools

AI Model Picker Quiz

Answer 7 questions and get personalized AI model recommendations — compare GPT, Claude, Gemini, Llama, and more

Open
API Dev Tools

Text & Code Diff Checker

Compare text, JSON, and YAML with structured change detection for reviews, debugging, and CI pipelines

Open
Formatter

SQL Formatter & Beautifier

Format, beautify, and minify SQL queries with keyword capitalization

Open
Generator

Favicon Generator

Generate favicons from text or emoji in all standard sizes with HTML and PWA manifest snippets

Open
AI Tools

System Prompt Library

Curated collection of system prompts for coding, writing, analysis, and more

Open
Converter

JSON to Go Struct

Convert JSON to idiomatic Go struct definitions with json tags, nested structs, omitempty, and pointer options

Open
Converter

JSON to Python Dataclass

Convert JSON to Python dataclass or TypedDict definitions with type hints, nested classes, and Optional types

Open
Converter

JSON to TypeScript Converter

Convert JSON to TypeScript interfaces and types with smart type inference, nested objects, and union types

Open
Converter

JSON to Zod Schema

Convert JSON to Zod schema definitions with optional/required inference, coerce mode, and nested schema support

Open
Converter

JSON to Kotlin Data Class

Convert JSON to Kotlin data classes with @Serializable annotations — supports kotlinx.serialization, Gson, and Moshi

Open
Converter

JSON to Rust Serde

Convert JSON to Rust structs with Serde derive macros — includes rename strategies, Option types, and field visibility control

Open
AI Tools

MCP Server Config Generator

Generate MCP server configurations for Claude Desktop, Cursor, and Windsurf with visual editor and presets

Open
Dev Tools

3-Way Diff & Merge Tool

3-way merge with conflict resolution — compare Base, Theirs, and Mine versions to resolve merge conflicts

Open
API AI Tools

JSON Schema Generator

Generate production-ready JSON Schemas from examples for function calling, structured output, and agent tool contracts

Open
Generator

CSS Gradient Generator

Visual gradient builder with live preview — create linear, radial, and conic gradients with color stops and CSS output

Open
AI Tools

Prompt Template Builder

Build AI prompt templates with variables, live preview, and export to JSON/YAML

Open
Dev Tools

Tailwind CSS Reference

Interactive Tailwind CSS cheat sheet with 430+ utilities — search, browse by category, view live previews, and copy class names

Open
Generator

Meta Tag Generator & Previewer

Generate SEO meta tags with live Google, Facebook, and Twitter card previews

Open
AI Tools

AI Cost Estimator

Estimate total AI API costs for real-world workloads across all major providers

Open
AI Tools

System Prompt Editor

Write and analyze AI system prompts with live token counting, variable detection, and XML highlighting

Open
Dev Tools

GraphQL Schema Viewer

Paste a GraphQL schema and explore types, fields, and relationships — no server needed, all client-side

Open
AI Tools

LLM Output Diff Tool

Compare outputs from different AI models side-by-side with diff highlighting

Open
AI Tools

AI Context Window Visualizer

Visualize how your AI model's context window is allocated across system prompt, tools, conversation, and RAG

Open
Generator

Test Data Generator

Generate realistic test data in JSON, CSV, and SQL — names, emails, addresses, and 18 types with custom schemas

Open
Formatter

Markdown Preview

Live Markdown preview with GitHub Flavored Markdown support

Open
Converter

YAML ↔ JSON Converter

Convert between YAML and JSON formats with validation and configurable formatting

Open
Converter

Text Case Converter

Convert text between camelCase, snake_case, PascalCase, kebab-case, and 10+ more formats instantly

Open
AI Tools

AI Prompt Tester & Comparator

Compare AI prompt variations side-by-side with token counting, diff highlighting, and variable tracking — test prompts before deployment

Open
Converter

TOML Editor & Converter

Parse, validate, and convert TOML to/from JSON and YAML — essential for Rust, Python, and config files

Open
Generator

Placeholder Image Generator

Generate custom placeholder images with configurable dimensions, colors, and text — download as PNG

Open
API Converter

Format Detective

Detect unknown data formats and convert between JSON, YAML, XML, CSV, TOML, and text with browser + API workflows

Open
Converter

CSV ↔ JSON Converter

Convert between CSV and JSON with auto-delimiter detection and proper escaping

Open
Dev Tools

API Header Builder & cURL Generator

Build HTTP requests visually and generate code for cURL, fetch, axios, and Python with headers, auth, and query params

Open
Dev Tools

JSONPath Tester

Test JSONPath expressions with real-time results — interactive JSON tree with click-to-path, syntax help, and examples

Open
Dev Tools

HTTP Status Code Reference

Interactive searchable reference for all HTTP status codes with descriptions and use cases

Open
Formatter

XML Formatter & Viewer

Format, beautify, and validate XML with syntax highlighting, tree view toggle, and minification

Open
Formatter

Log Parser & Highlighter

Parse and analyze logs with syntax highlighting, level filtering, and search. Auto-detects JSONL, Python, syslog, nginx formats

Open
Dev Tools

NDJSON/JSONL Viewer

Parse and view JSONL (newline-delimited JSON) with interactive table, filtering, sorting, and export

Open
API Converter

Markdown to HTML Converter

Convert Markdown ↔ HTML with GitHub Flavored Markdown support, clean output, and optional API automation

Open
AI Tools

Prompt Token Budget Planner

Plan your AI system prompt token budget visually across sections against model context limits

Open
Dev Tools

IP & Subnet Calculator

Calculate subnets, CIDR ranges, network addresses, and host counts for IPv4 with visual binary breakdown

Open
AI Tools

AI Tool Schema Builder

Visual schema builder for AI tool definitions with export to OpenAI, Anthropic, MCP, and JSON Schema formats

Open
Generator

Nginx Config Generator

Generate nginx configurations for reverse proxy, SSL, static sites, and load balancers with security headers

Open
Converter

Base64 Encoder/Decoder

Encode and decode Base64 strings and files

Open
Converter

URL Encoder/Decoder

Encode and decode URL components and full URLs

Open
Converter

Unicode Character Inspector

Inspect any text character-by-character: code points, UTF-8/16/32 bytes, HTML entities, JS escapes, and Unicode categories

Open
Converter

Unix Timestamp Converter

Convert between Unix timestamps and human-readable dates

Open
Formatter

JavaScript Minifier & Beautifier

Minify or beautify JavaScript code with compression ratio stats

Open
Formatter

CSS Minifier & Beautifier

Minify or beautify CSS with size reduction stats and comment removal options

Open
Formatter

HTML Formatter & Viewer

Format, beautify, and validate HTML with live preview, syntax highlighting, and minification

Open
API AI Tools

LLM Structured Output Validator

Validate structured outputs and tool schemas for OpenAI, Anthropic, MCP, and JSON Schema with detailed errors and fix guidance

Open
Dev Tools

SSH Config Generator

Generate SSH config files with jump hosts, port forwarding, and identity keys — visual editor with presets

Open
Converter

OpenAPI to TypeScript Generator

Generate TypeScript types and API clients from OpenAPI 3.x specs — handles $ref, allOf, oneOf, discriminators

Open
Dev Tools

Shell Command Explainer

Break down and explain shell commands with annotated syntax highlighting and dangerous pattern detection

Open
Dev Tools

YAML/JSON5 Config Validator

Validate YAML, JSON5, and JSON configs with instant error detection, linting, and format conversion

Open
Dev Tools

Webhook Payload Inspector

Analyze webhook payloads with formatted JSON view, HMAC signature verification, timestamp detection, and cURL reconstruction

Open
Generator

robots.txt Generator & Validator

Generate and validate robots.txt with user-agent rules, sitemap URLs, and AI scraper blocking — download or copy instantly

Open
Generator

Git Commit Message Generator

Generate conventional commit messages with proper formatting — supports types, scopes, breaking changes, and issue references

Open
Generator

ASCII Art Generator

Convert text to ASCII art with 10 unique fonts — perfect for README files, terminal banners, and code comments

Open
Converter

HTML Entity Encoder

Encode and decode HTML entities and special characters

Open
Converter

Image to Base64 Converter

Convert PNG, JPG, GIF, WebP, and SVG images to Base64 encoding with data URI, CSS, and HTML formats

Open
Converter

Number Base Converter

Convert between hex, binary, decimal, and octal with bit visualization and bitwise operations

Open
Converter

Byte & Data Unit Converter

Convert between bytes, KB, MB, GB, TB with SI and binary standards — includes transfer time estimator

Open
Dev Tools

JSON Sorter & Cleaner

Sort JSON keys, remove null values, deduplicate arrays, flatten nested objects — multiple operations in one tool

Open
Dev Tools

Glob Pattern Tester

Test glob patterns against file paths with real-time matching — supports gitignore, tsconfig, and shell syntax

Open
Generator

UUID Generator

Generate UUID v4 and UUID v7 with bulk output and format controls

Open
AI Tools

Markdown Memory File Builder

Create structured markdown memory files for AI agents — SOUL.md, USER.md, AGENTS.md, daily logs, decision records, and more

Open
Dev Tools

API Response Mocker

Generate mock API responses for testing — get instant code for fetch, MSW, Express, curl, and Python without spinning up a server

Open
AI Tools

Embedding Similarity Calculator

Calculate cosine similarity, dot product, and distance between embedding vectors from OpenAI, Cohere, and more

Open
AI Tools

RAG Chunk Size Calculator

Calculate optimal chunk size and overlap for RAG pipelines based on document type and embedding model

Open
AI Tools

Agent Trace Viewer

Visualize AI agent execution traces with timeline, table, and detail views for debugging LangChain and OpenAI agents

Open
AI Tools

Prompt Version Diff

Compare AI prompt versions with semantic diff — track variable changes, instruction modifications, and token deltas

Open
AI Tools

AI Guardrail Rule Tester

Build and test AI guardrail rules with instant feedback — preset PII, injection, and safety patterns

Open
AI Tools

Function Call Flow Simulator

Simulate AI function calling and tool use flows without API calls — test multi-step agent conversations

Open
Converter

OpenAI ↔ Anthropic Format Converter

Convert between OpenAI and Anthropic API formats — messages, tool definitions, and responses bidirectionally

Open
Dev Tools

chmod Calculator

Visual Unix permission calculator with bidirectional numeric and symbolic chmod conversion

Open
Dev Tools

Env File Manager

Parse, validate, edit, and convert .env files between JSON, YAML, Docker, and Shell formats

Open
AI Tools

AI API Key Tester

Validate AI API keys from Anthropic, OpenAI, OpenRouter, Groq, and more — detect provider, check format, get config snippets

Open
Dev Tools

Cron Expression Tester

Test cron expressions and see next run times in your timezone. Generate cron from natural language like 'every Monday at 9am'. Free, private, no signup.

Open
Generator

Markdown Table Generator

Visual spreadsheet-like table editor that outputs clean Markdown tables with CSV import and alignment controls

Open
Generator

htaccess Generator

Visual Apache .htaccess file generator with redirects, rewrites, security headers, caching rules, and access control

Open
Generator

launchd Plist Generator

Visual macOS launchd plist XML file generator for daemons and scheduled tasks with calendar intervals and install commands

Open
Dev Tools

Hash Generator

Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes for text or files

Open
Generator

Lorem Ipsum Generator

Generate placeholder text in various formats

Open
AI Tools

AI Token + Pricing Calculator

Paste text, count tokens, and compare LLM API costs across GPT, Claude, Gemini and more with batch estimation and CSV export

Open
Dev Tools

ENV File Validator

Validate .env files against .env.example — catch missing variables, empty values, and type mismatches

Open
Dev Tools

Environment Variable Generator

Generate .env files from Docker Compose, Kubernetes configs, or framework presets. Create documented environment variable templates instantly.

Open
Dev Tools

System Design Simulator

Visual drag-and-drop system architecture builder with components, connections, templates, and export — perfect for interview prep

Open
AI Tools

WebMCP Playground

Test and validate WebMCP tool definitions — paste manifest JSON, simulate agent tool calls, validate against the W3C spec, preview tool discovery.

Open
AI Tools

MCP Server Starter Generator

Generate complete MCP server projects with tools, resources, and auth — TypeScript, Python, or Go

Open
Dev Tools

Extension Guard

Scan Chrome extension permissions for security risks with risk scoring, dangerous combination detection, and plain-English explanations

Open
Dev Tools

URL Metadata Extractor

Extract OG tags, canonical URLs, meta descriptions, and JSON-LD from pasted HTML

Open
Dev Tools

Website Tech Stack Detector

Detect website frameworks and platforms from pasted HTML, headers, and script URLs

Open
Dev Tools

RSS Feed Validator

Validate RSS/Atom XML and preview feed entries with parser diagnostics

Open
Dev Tools

DNS Lookup Parser

Parse dig and nslookup output into structured DNS record views

Open
Dev Tools

HTTP Header Inspector

Inspect HTTP response headers for security, caching, and CORS posture

Open
Dev Tools

SSL Certificate Checker

Parse certificate text and check issuer, SANs, and expiry risk

Open
AI Tools

Cursor Rules Generator

Generate .cursorrules and .windsurfrules files for AI coding assistants

Open
AI Tools

AI Response Comparator

Compare model outputs side-by-side with diff and analysis modes

Open
Dev Tools

OpenAPI Changelog Generator

Generate endpoint-level changelogs by diffing two OpenAPI specs

Open
Dev Tools

Webhook Signature Verifier

Verify webhook signatures and inspect payload integrity before processing

Open
Dev Tools

.gitignore Generator

Generate stack-aware .gitignore templates for modern projects

Open
Dev Tools

Package.json Generator

Generate package.json scaffolds for apps and libraries

Open
Dev Tools

License Compatibility Checker

Check whether open source licenses are compatible and get recommended outbound licenses

Open
Dev Tools

Semver Calculator

Compare semantic versions and test range expressions

Open
Dev Tools

Dockerfile Generator

Generate safer Dockerfile templates for Node, Python, and Go

Open
Generator

README Generator

Generate clean README.md templates with project structure and usage sections

Open
Dev Tools

CORS Debugger

Analyze CORS failures and output concrete server-side fixes

Open
Dev Tools

API Key Generator

Generate secure, format-aware API keys and tokens for local development, testing, and CI pipelines. Supports custom lengths, prefixes, and character sets.

Open
Converter

Tailwind Previewer

Preview Tailwind utility output and conversion results

Open
Dev Tools

Regex Tester & Explorer

Test and explore regex patterns with live matches, capture groups, and flags

Open
Dev Tools

JSON Patch Builder

Build RFC 6902 patch arrays from source and target JSON

Open
Dev Tools

ENV Template Generator

Generate structured .env templates and environment docs

Open
Dev Tools

GraphQL Query Builder

Build GraphQL queries and mutations from field and variable inputs

Open
Dev Tools

Validation Schema Generator

Generate validation schemas from representative JSON examples

Open
Generator

Changelog Generator

Generate categorized changelog documents from commit lists

Open
AI Tools

System Prompt Analyzer

Analyze system prompts for clarity, structure, and token posture

Open
AI Tools

MCP Tool Tester

Validate and test MCP/WebMCP tool definitions

Open
Dev Tools

Rate Limit Calculator

Calculate allowed throughput and headroom for API quotas

Open
Dev Tools

OAuth Playground

Generate OAuth authorization URLs and token exchange requests

Open
AI Tools

Web-to-Markdown Converter

Convert webpage HTML to markdown and estimate token savings

Open
Dev Tools

Color Contrast Checker

Check WCAG 2.1 color contrast ratios between foreground and background colors. Shows AA/AAA pass/fail for normal and large text.

Open
Generator

CSS Animation Generator

Visual CSS keyframe animation builder. Define keyframes, set timing functions, duration, delay, iteration count. Live preview and copy generated CSS.

Open
Converter

CSS Units Converter

Convert between CSS units: px, rem, em, vw, vh, %, and pt. Bidirectional with configurable base font size and viewport dimensions.

Open
Dev Tools

CSS Specificity Calculator

Calculate and visualize CSS selector specificity. Paste selectors to see specificity scores, compare multiple selectors, and understand which styles win.

Open
Converter

cURL Converter

Convert cURL commands to JavaScript fetch, Axios, Python requests, Node.js http, PHP, and Go. Supports headers, JSON body, form data, and auth.

Open
Generator

CSS Text Shadow Generator

Build and preview CSS text-shadow effects interactively. Stack multiple shadow layers, use presets like neon or retro, and copy the ready-to-use CSS.

Open
Dev Tools

Basic Auth Encoder / Decoder

Encode and decode HTTP Basic Authentication credentials. Generate the Authorization header or curl flag from username and password, or decode a token back to plaintext.

Open
Dev Tools

HTTP Cookie Builder

Build and validate Set-Cookie headers interactively. Configure all cookie attributes — Secure, HttpOnly, SameSite, Path, Domain, Expires, Max-Age, Partitioned.

Open
Dev Tools

Word & Character Counter

Count words, characters, sentences, paragraphs, and lines. Get instant reading time and speaking time estimates, plus top word frequency analysis.

Open
AI Tools

AI Code Smell Detector

Detect AI-generated code anti-patterns — hallucinated imports, over-abstraction, verbose error handling, redundant logic, and AI tells. Instant scored analysis.

Open
AI Tools

LLM Workflow Cost Calculator

Model multi-step AI pipelines — embed, retrieve, generate, validate — and see total cost per execution across providers with caching simulation.

Open
AI Tools

Codebase Context Packer

Pack code files into optimized LLM context with smart truncation, token budgeting, and XML/markdown/plain output formats. Ready to paste into Claude or GPT.

Open
AI Tools

AI Prompt Injection Tester

Test system prompts against 50+ known injection attack patterns — role hijacking, instruction override, delimiter abuse, encoding attacks, and jailbreaks.

Open
AI Tools

AI API Error Decoder

Paste an error response from Claude, OpenAI, Gemini, or Mistral API — get a human-readable explanation, fix with code snippet, and retry strategy.

Open
AI Tools

AI Agent Cost Simulator

Configure multi-agent architectures and visualize cost explosion curves. Compare multi-agent vs single-agent with context growth modeling and monthly projections.

Open
Dev Tools

.env Security Scanner

Detect exposed API keys, high-entropy secrets, and insecure defaults in .env files. Recognizes 40+ key formats from OpenAI, AWS, Stripe, GitHub, and more.

Open
Converter

OpenAPI to MCP Generator

Convert OpenAPI 3.x specs into MCP tool definitions — one tool per endpoint with proper input schemas. Export as config JSON, TypeScript, or Python server.

Open
AI Tools

AI Rules Linter

Lint CLAUDE.md, .cursorrules, and copilot-instructions files for redundancy, conflicting instructions, missing sections, and token efficiency.

Open
AI Tools

Git Diff Token Counter

Paste a git diff and see token counts per file, cost across AI models for code review, and chunking suggestions when diffs exceed context limits.

Open
AI Tools

LLM Latency Estimator

Estimate time-to-first-token, generation time, and total latency for any AI model. Get UX recommendations for spinners, streaming, and background jobs.

Open
AI Tools

Prompt A/B Test Designer

Design rigorous prompt experiments with sample size calculation, statistical significance, cost estimation, and evaluation framework export.

Open
AI Tools

MCP Permission Auditor

Audit MCP server configurations for security risks — permission surface analysis, risk scoring, dangerous capability combinations, and least-privilege recommendations.

Open
AI Tools

AI Doc Readability Scorer

Score documentation for human and AI-agent readability across 6 dimensions — structure, code examples, API discoverability, schema coverage, LLM parseability.

Open
AI Tools

AI Model Sunset Tracker

Track AI model deprecation dates, migration paths, and breaking changes across OpenAI, Anthropic, Google, Meta, and Mistral. Filterable and searchable.

Open
Generator

TSConfig Builder

Visually compose tsconfig.json with target, module, strictness, paths, project references. Live JSON preview, copy to clipboard, with explanations of each compiler option.

Open
Generator

ESLint Flat Config Builder

Build modern eslint.config.js (flat config) with rule presets, plugin imports, file-glob overrides, and ESM output. Includes legacy .eslintrc to flat-config migration.

Open
Generator

Biome Config Builder

Compose biome.json for the Biome formatter and linter with formatter, linter, organize-imports, and per-rule severity. Side-by-side comparison against an equivalent ESLint+Prettier setup.

Open
Generator

Prettier Config Builder

Build .prettierrc with options (printWidth, tabWidth, semi, singleQuote, trailingComma, etc.) and a live formatted-code preview showing how each option affects sample code.

Open
Generator

Vite Config Builder

Compose vite.config.ts with framework presets (React/Vue/Svelte/Astro), plugins, server options, build options, and SSR/library mode. Outputs typed TypeScript.

Open
Generator

Bun Config Builder

Build bunfig.toml plus Bun-flavored package.json scripts. Includes a Node.js to Bun migration assistant flagging the known incompatibility surface (sqlite, vm, cluster, etc.).

Open
Generator

Wrangler TOML Builder

Compose Cloudflare Workers wrangler.toml or wrangler.jsonc with bindings (KV, D1, R2, Durable Objects, Queues, Hyperdrive), routes, vars, compatibility flags, and triggers. Outputs TOML and JSONC side-by-side.

Open
Generator

Deno Permissions Builder

Visually select Deno --allow-* flags (read, write, net, env, run, sys, ffi, hrtime), build deno.json/deno.jsonc tasks, and produce the equivalent CLI invocation. Explains permission scope per flag.

Open
Generator

Systemd Unit Builder

Build systemd .service, .timer, and .socket unit files with directives for Type, ExecStart, User, Restart, Environment, After, WantedBy. Validates required directives and outputs ready-to-install unit.

Open
Generator

Caddyfile Builder

Build a Caddy v2 Caddyfile with reverse-proxy, file-server, redirect, header, route, and TLS directives. Multi-site composition with snippets, named matchers, and generated environment-specific overrides.

Open
Dev Tools

Dockerfile Linter

Lint Dockerfiles against hadolint-style rules: latest-tag pins, layer-cache misses, apt-get install patterns, root user, missing HEALTHCHECK, COPY vs ADD, multi-stage opportunities. Gives severity badges and fix snippets.

Open
Dev Tools

DB Connection String Parser

Parse and build connection strings for PostgreSQL, MySQL, MongoDB (incl. SRV), Redis, and SQL Server. Exposes host, port, auth, database, params, SSL options, and reconstructs masked-credential and url-encoded variants.

Open
Dev Tools

Kubernetes YAML Validator

Paste Kubernetes manifests (Deployment, Service, Ingress, ConfigMap, StatefulSet, Job, CronJob) and run structural plus semantic validation: required fields, apiVersion match, image pull secrets, resource limits, security context. Runs entirely in your browser with an embedded schema.

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Dev Tools

Helm Values Diff

Diff Helm values.yaml between dev, staging, and prod environments. Surfaces added, removed, and changed keys, traces override sources, and shows the merged effective values per environment. Pure deep-diff, no chart rendering required.

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Formatter

Terraform HCL Formatter

Format and lint Terraform HCL with module, variable, and output structure validation. Detects common mistakes including hardcoded credentials, wildcard policies, and missing required variables, plus terraform fmt-equivalent indentation and equals alignment.

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Dev Tools

AWS IAM Policy Analyzer

Paste an IAM policy JSON to get wildcard warnings, action expansion counts (how many AWS permissions a wildcard actually grants), resource ARN risk scoring, and least-privilege diff hints. Embedded action catalog covering IAM, S3, EC2, KMS, and more.

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Dev Tools

AWS ARN Parser

Decompose any AWS ARN into partition, service, region, account, resource type, and resource ID. Build ARNs from form fields with copy-to-clipboard. Covers IAM, S3, Lambda, EC2, RDS, DynamoDB, SQS, SNS, KMS, ECR, and EKS with embedded format references.

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AI Tools

Fine-Tuning JSONL Validator

Validate OpenAI and Anthropic supervised fine-tuning JSONL line-by-line: schema, role ordering (system→user→assistant), token counts via gpt-tokenizer, message-format violations, and duplicate detection. Reports per-row issues plus summary stats.

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Converter

Chat Format Converter

Convert chat-completion JSON between OpenAI Chat Completions, Anthropic Messages, Google Gemini, and Mistral with role and content-block remapping. Bidirectional with tool-use and image-content handling notes.

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AI Tools

Prompt Cache ROI Calculator

Given prompt structure (static prefix tokens, query tokens, calls per day, model), compute Anthropic and OpenAI prompt-caching breakeven and projected monthly savings vs no-cache. Embedded June 2026 pricing for Claude Fable 5, Opus 4.8, Sonnet 4.6, Haiku 4.5, GPT-4o, and GPT-4o-mini.

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AI Tools

LLM Judge Rubric Builder

Build LLM-as-judge rubric YAML or JSON with weighted criteria, scoring scales (Likert 1-5, pass/fail, percentage), judge-prompt scaffolding, and rubric self-validation that checks weights sum to 1.0 and scales stay consistent.

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AI Tools

Eval Dataset Builder

Compose golden eval JSONL with prompt, expected, category, and tag fields. Includes deduplication, balance-by-category checks, and exporters for OpenAI Evals, Promptfoo, and DeepEval format.

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Dev Tools

SSE Stream Replayer

Paste a Server-Sent Events log from any provider, parse event and data frames, and replay token-by-token at 0.25x to 4x speed with a timing chart and event-type breakdown.

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AI Tools

Anthropic Stream Event Viewer

Decodes Anthropic message_stream typed events (message_start, content_block_start/delta/stop, tool_use, thinking, message_delta, message_stop) and reconstructs the conversation, stop_reason, and per-call token-usage breakdown including cache write and cache read counts.

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Generator

CSS Grid Generator

Visually compose grid-template-columns, rows, and named areas. Click cells to paint regions, drag tracks, and copy minimal CSS plus matching Tailwind utility classes.

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Dev Tools

Container Query Playground

Live editor for CSS @container rules. Resize the parent visually, watch component breakpoints flip, and copy the exact named-container CSS for your codebase.

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Dev Tools

View Transitions Playground

Trigger View Transitions API animations live in your browser — fade, slide, scale, morph, flip — and copy the HTML+CSS+JS snippet including cross-document @view-transition.

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Generator

Tailwind v4 Theme Builder

Compose a Tailwind v4 @theme block with design tokens — colors, spacing, fonts, breakpoints, container sizes — preview swatches and dark-mode pairing, export the CSS variable bundle.

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Dev Tools

Playwright Selector Builder

Paste HTML, build getByRole/getByText/getByLabel/CSS/XPath locators, see hit count and a stability score for brittle selectors, copy the ready-to-paste TypeScript snippet.

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Dev Tools

Protobuf Decoder

Decode binary protobuf payloads with optional .proto schemas. Inspect field tags, wire types, and nested messages.

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Converter

Drizzle ↔ Prisma Schema Converter

Convert Drizzle ORM schemas to Prisma and back, with parity reports for tables, columns, relations, and indexes.

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Dev Tools

OTel Trace Viewer

Visualize OpenTelemetry traces (OTLP JSON or Jaeger) as a waterfall flame graph with span attributes, errors, and per-service summaries.

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Dev Tools

HAR File Analyzer

Drop a HAR file and inspect waterfall, blocking, headers, third-party breakdown, slow resources, and total transfer time — entirely in your browser.

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Dev Tools

WebSocket Tester

Connect to ws:// or wss:// endpoints with the native browser WebSocket API. Send and receive frames in JSON, text, or hex.

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Generator

MSW Handler Builder

Visually compose Mock Service Worker REST and GraphQL handlers with matchers, response shapes, delays, and one-shot semantics. Exports MSW v2 handlers.ts.

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Converter

Slug Generator

Convert any title or text into a clean URL-safe slug with transliteration, separators, and length control. No signup required, 100% private.

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Generator

Modern ID Generator

Generate UUIDv7, ULID, and NanoID identifiers in bulk and decode the embedded timestamp from sortable IDs. No signup required, 100% private.

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Generator

CSS clamp() Generator

Generate a CSS clamp() value for fluid, responsive typography or spacing from min/max sizes and a viewport range. No signup required, 100% private.

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Dev Tools

Aspect Ratio Calculator

Calculate aspect ratios and proportionally scale width/height, with common presets and a CSS aspect-ratio output. No signup required, 100% private.

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Generator

Cubic Bezier Editor

Visually edit a CSS cubic-bezier() easing curve with draggable control points, presets, and a live animation preview. No signup required, 100% private.

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Converter

XML to JSON Converter

Convert XML to JSON and JSON back to XML in the browser, with attribute handling and pretty-printing. No signup required, 100% private.

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Dev Tools

HMAC Generator

Compute an HMAC for any message and key (SHA-1/256/384/512) and generate webhook signatures in common provider formats. No signup required, 100% private.

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Dev Tools

JWT Generator

Build and sign a JSON Web Token (HS256/384/512) entirely in your browser with editable header and claims. No signup required, 100% private.

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Generator

EditorConfig Generator

Generate a .editorconfig file with root and per-filetype rules for indentation, charset, line endings, and whitespace. No signup required, 100% private.

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Generator

Markdown TOC Generator

Generate a nested Markdown table of contents from your document headings with GitHub-style anchor links. No signup required, 100% private.

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Dev Tools

IPv6 Expander & Validator

Expand, compress, and validate IPv6 addresses and show prefix/network details for a CIDR. No signup required, 100% private.

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Generator

Sitemap.xml Generator

Generate a valid sitemap.xml from a list of URLs with lastmod, changefreq, and priority. No signup required, 100% private.

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Generator

Gitattributes Generator

Generate a .gitattributes file for line-ending normalization, binary files, Git LFS, and linguist overrides. No signup required, 100% private.

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Generator

Diceware Passphrase Generator

Generate strong, memorable passphrases from a curated wordlist using cryptographically secure randomness. No signup required, 100% private.

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Generator

Cache-Control Builder

Build an HTTP Cache-Control header from directives with plain-language explanations of each option. No signup required, 100% private.

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AI Tools

AGENTS.md Generator

Generate a best-practice AGENTS.md file for coding agents with command-first sections, conventions, and verifiable done-criteria. No signup required, 100% private.

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AI Tools

llms.txt Generator

Generate a spec-compliant llms.txt file to guide AI assistants and IDE agents to your most important documentation. No signup required, 100% private.

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AI Tools

Token & Whitespace Inspector

Visualize tokenization boundaries and reveal hidden whitespace and unicode gotchas in a prompt. No signup required, 100% private.

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AI Tools

JSON Schema Example Generator

Generate a valid example JSON payload from a JSON Schema, honoring types, enums, required fields, and formats. No signup required, 100% private.

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Dev Tools

Bcrypt Generator & Verifier

Generate and verify bcrypt password hashes entirely in your browser with an adjustable cost factor. No signup required, 100% private.

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Converter

SVG to JSX Converter

Convert an SVG into a clean React/JSX component with camelCased attributes, prop forwarding, and currentColor. No signup required, 100% private.

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Dev Tools

Homoglyph & Invisible Character Detector

Detect zero-width characters, bidi overrides, and homoglyph look-alikes in text or code to catch spoofing and hidden-instruction attacks. No signup required, 100% private.

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Developer Tool Directory

AI Dev Hub is a browser-based toolkit with 250+ utilities plus free REST APIs for developers, AI builders, and technical teams. Common workflows include data formatting, API prototyping, prompt engineering, model cost estimation, schema validation, and agent tool orchestration.

Browse by category: Dev Tools, AI Tools, Formatters, Converters, Generators. For LLMs and agents, machine-readable indexes are available at /api/tools.json, /api/tools-index.json, /llms-full.txt, and /.well-known/webmcp.json. For API and agent integrations, see /agents/.