space4.dev
JSONFormatter.org
JSONLint
Tempreon
ChainMemory
Memori
Agentmemory
OpenMemory MCP
TheSecondBrain.dev
cognee
VATES.jp
space4.dev is a free collection of 70+ developer tools built for speed and privacy. It covers JSON formatting, validation, and conversion (to YAML, XML, CSV, TypeScript, Java, C#, and more), Base64/URL/HTML/Unicode encoding and decoding, JWT decoding and inspection, Unix timestamp conversion, cron expression parsing and generation, and OpenAPI/Swagger viewing, validation, and diffing.
Every tool runs 100% client-side in the browser โ nothing you paste or upload is ever sent to a server. That makes it safe to use with sensitive data like auth tokens, API responses, or internal config files, which most competing tool sites don't guarantee.
No signup, no ads, and no account walls โ each tool has its own dedicated, fast-loading page so you can jump straight to what you need instead of digging through a cluttered all-in-one dashboard.
Tempreon is a personal memory layer for your AI tools, connected over MCP. Your knowledge, preferences, and decisions travel across Claude, ChatGPT, Cursor, and any MCP-capable client โ captured once, available everywhere. It learns how you actually work instead of just storing what you said.
space4.dev
TempreonNo features have been listed yet.
Tempreon's answer:
Tempreon started with a simple observation: AI models keep changing, but the thing that makes them useful to you โ your context, your preferences, your judgment โ gets rebuilt from scratch inside every tool, and lost every time you move.
We built the layer that fixes that: person-owned memory served over the open Model Context Protocol, so it works across assistants instead of belonging to one. Along the way we open-sourced the pieces that are useful to everyone regardless of whether they use Tempreon โ like memhaul, our MIT-licensed CLI for turning ChatGPT and Claude data exports into files you own.
The through-line is custody: the model is temporary, your memory shouldn't be.
Tempreon's answer:
Most alternatives in this space are memory infrastructure for developers building their own AI apps. If you're the person using several AI tools every day, that's not your problem โ your problem is re-explaining yourself to each of them and losing everything when you switch.
The choice is really about who the memory is for. Ours is for you.
Tempreon's answer:
Tempreon is built for the person, not the app. Most memory products are developer APIs for adding memory to a single product; Tempreon is a memory layer you own that travels with you across every AI tool you use โ Claude, ChatGPT, Cursor, anything MCP-capable.
Tempreon's answer:
Individuals who live in AI tools all day: operators, consultants, founders, sales professionals, and knowledge workers who use more than one assistant and are tired of being a stranger to each of them.
If you've ever pasted the same context into Claude and ChatGPT in the same week โ you're the audience.
Tempreon's answer:
The protocol choice is the product decision: build on the open standard, and your memory works everywhere the standard does.
JSONFormatter.org - Online JSON Formatter and JSON Validator will format JSON data, and helps to validate, convert JSON to XML, JSON to CSV. Save and Share JSON
ChainMemory - Portable, verifiable memory for AI agents โ works across ChatGPT, Claude, Gemini and any MCP client
JSONLint - JSON Lint is a web based validator and reformatter for JSON, a lightweight data-interchange format.
Memori - Persistent memory from agent trace, not just conversation