coldHat
Put on anyone's AI rules by GitHub username: fetches their hat.md and its hat code.
Install
Add this to your client's MCP configuration (Claude Desktop: claude_desktop_config.json; Cursor: .cursor/mcp.json; VS Code and others use the same "mcpServers" shape).
claude mcp add --transport http coldhat 'https://coldhat.f-keys.com/mcp'{
"mcpServers": {
"coldhat": {
"type": "http",
"url": "https://coldhat.f-keys.com/mcp"
}
}
}Documentation
From the project's README on GitHub, refreshed weekly. Links open on GitHub.
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║ will another model keep your rules? ║
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╚════════════════════════════════════════════════════════════════════════════════════════════╝coldHat puts working rules on any AI chat in one line. Type this into Claude, ChatGPT or Grok:
open sesame coldhat.f-keys.com/u/vince-gonzalez/frontierThe assistant reads the hat, answers with its hat code to prove it read it, and works by those rules for the rest of the chat. Live at coldhat.f-keys.com.
Every hat ends with a seal. If the assistant can't quote it, the hat was cut off, and it tells you.
Addresses
| You want to | Type this after open sesame |
|---|---|
| Wear a person's hat | coldhat.f-keys.com/u/<github-user> or .../u/<github-user>/<hat> |
| Wear one of Fabric's patterns | coldhat.f-keys.com/fabric/extract_wisdom |
| Wear a prompts.chat prompt | coldhat.f-keys.com/prompts/linux-terminal |
| Stack up to three, later layers winning | coldhat.f-keys.com/u/vince-gonzalez/editor+fabric/analyze_claims |
| Merge a stack by slot instead of piling it up | coldhat.f-keys.com/amp/fabric/extract_ideas+fabric/analyze_claims |
| Keep rules no other layer can override | put them under ## Locked in your hat |
| Wear one exact version | coldhat.f-keys.com/u/<user>/<hat>@<commit> |
| Check a reply wore the current hat | coldhat.f-keys.com/verify?address=<hat address> with the reply |
Every reply starts with the hat mark and code, for example 🎩💨⛄🔬 Hat's on · b7d19023:
a top hat, a gust, Frosty, then one icon per layer.
Apps that take connectors can add https://coldhat.f-keys.com/mcp once and call any of
these by name (tools wear_hat and wear_stack). A chat that can't browse can still wear
a hat: Copy hat on coldhat.f-keys.com, then paste.
Starter hats
| Hat | Type this |
|---|---|
| Code reviewer: verdict first, findings by severity with line, failure and fix | open sesame coldhat.f-keys.com/u/vince-gonzalez/reviewer |
| Grant writer: rubric first, every number sourced, every limit met | open sesame coldhat.f-keys.com/u/vince-gonzalez/grants |
| Plain-English editor: shorter, clearer, still your voice | open sesame coldhat.f-keys.com/u/vince-gonzalez/editor |
| Frontier: mechanical register, rules over manners | open sesame coldhat.f-keys.com/u/vince-gonzalez/frontier |
Make your own
A hat is a hat.md in a public GitHub repository named coldhat, so only its owner can
change it. Extra hats go in hats/<name>.md and live at /u/<user>/<name>. Write one at
coldhat.f-keys.com/make, bring the instructions you
already keep for other assistants at coldhat.f-keys.com/import,
or start from coldhat-starter.
Facts under ## Status carry a date and a shelf life
(- label: value · as of YYYY-MM-DD · check after N days). The server checks them against
today, and the assistant asks about any that have gone stale before using them.
Measured, not assumed
Safety
A hat is instructions, not a credential, and open sesame is not a password. Every hat
page tells the assistant to ignore it unless the person asked for it, and never to ask for
passwords, keys, codes or payment details. Layers from Fabric and prompts.chat credit their
authors; prompts written to make a model drop its rules are not served.
Report a hat.
The coldHat server and merge engine are proprietary. This repository holds the public hats, the format, and the results.
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║ · C R E A T I V E · ║
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║ ──────────────────────────────────────── ║
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║ Vincent Gonzalez ║
║ f-keys.com ║
║ ORCID 0009-0005-3640-014X ║
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╚════════════════════════════════════════════════════════════╝Part of F-Keys — independent hardware, software and internet products. See the working log and live status.
Frequently asked questions
What is coldHat?
Put on anyone's AI rules by GitHub username: fetches their hat.md and its hat code.
How do I install coldHat?
It runs as a remote server. In Claude Code: claude mcp add --transport http coldhat 'https://coldhat.f-keys.com/mcp'. For other clients, paste the JSON configuration from this page into their MCP settings.
Does coldHat need an API key?
Its registry entry lists no required key or secret. Some features may still need an account with the service it connects to.
Is coldHat open source?
Its code is public on GitHub, but the repository does not declare a standard license.
Who maintains coldHat?
It is published by vince-gonzalez. AI.tn lists it but does not maintain or endorse it.
From the official MCP Registry. Listing is not an endorsement: review a server's code and permissions before giving it access to your data.