Agent-Native Calendar
by BuilderIO
Agent-Native Google Calendar - manage events, sync, and public booking
Runs in the cloud★ 7,620MITUpdated 2 months ago
Install
Krewbill
Overview
Description from the maker (original English)
Per-client shared AI memory: approved notes that Claude, ChatGPT and Cursor read over MCP.
PopNx MCP’s three pillars
These three are never merged into one score: opinions, measurements and popularity are different things.
- User voiceiNo reviews yetReviews open together with accounts in a later step
- Our basic checksi2 of 3 passedChecked from public information; code not scanned yet
- UsageiNot measured yet★ –
What you can do with it
We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.
- Connection: Runs in the cloud
- Transport: Streamable HTTP
- Category: Docs, sheets & office work
- You need to fill in: Authorization
Install
Pick the AI app you use, then copy the settings.
Before you install
- Basic checks: 2 of 3 passed
- Runs on the maker’s server: what you ask it goes through their server.
- You fill in yourself:
Authorization
Values marked secret are keys to your account. Never share them or paste them into a chat.
You need
- Runs in the cloudNothing to install; it connects over the internet
Which app do you use?
Pick your app above. We remember it, so next time the button says “Install in …”.
This address needs a key in a request header, which the add-connector menu cannot set. Use Claude Code, Cursor or VS Code instead.
Run this in your terminal
claude mcp add --transport http krewbill https://www.krewbill.com/api/mcp --header 'Authorization: your-value'Fill in the empty values before running it.
Or copy the settings yourself
Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"krewbill": {
"url": "https://www.krewbill.com/api/mcp",
"headers": {
"Authorization": "your-value"
}
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
Or copy the settings yourself
Paste into .vscode/mcp.json in your project
{
"servers": {
"krewbill": {
"type": "http",
"url": "https://www.krewbill.com/api/mcp",
"headers": {
"Authorization": "your-value"
}
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
This address needs a key in a request header, which the add-connector menu cannot set. Use Claude Code, Cursor or VS Code instead.
Your choice stays on this device in a cookie; no account needed.
Values you fill in
Authorizationsecret required HTTP headerBearer followed by your Krewbill connection key
These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.
What it can do
The server asks you to sign in before it lists its tools.
Basic checksi
We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 8, 2026
- ✓ Pass
Maker matches the repo
The registry name was verified with the GitHub account RyanV1304, which owns the repo
- … Not checked yet
Still maintained
We have not read this repo from GitHub yet
- … Not checked yet
Has a licence
We have not read this repo from GitHub yet
- ✓ Pass
Endpoint responds
Responded in 570 ms (HTTP 401)
- ! Caution
Sign-in with OAuth
Needs a key or token that you copy and paste yourself
- … Not checked yet
No hidden instructions in tool descriptions
Not checked yet; we read the tool list when we check the endpoint
Compared with others in Docs, sheets & office worki
- More stars than 0% of the other 3544 servers in this category
- Published to the registry more recently than 78% of the other 3544 servers in this category
- Basic checks equal to or better than 39% of the other 3544 servers in this category
Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.
Common questions
Is Krewbill safe?
It passed 2 of 3 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.
What keys or codes does it need?
You need to fill in: Authorization
Does it run on my computer or in the cloud?
It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.
Is it still maintained?
The GitHub repo last changed –, and the latest version (0.1.0) reached the registry 8 days ago.
Which apps can use it?
Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.
What can I use instead?
In the same category: Agent-Native Calendar, Excel MCP Server, MCP Server for Excel
Alternatives
Servers in the same category from other makers, sorted by stars.
Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi
Excel MCP Server
by haris-musa
Lets AI create and edit Excel files itself, including formulas, charts and PivotTables, without Excel installed.
Runs on your computer★ 4,276MITUpdated 7 days ago
Install
MCP Server for Excel
by sbroenne
Excel automation for AI - Sheets, Power Query, DAX, VBA, Tables, Ranges and more. Windows only.
Runs on your computer★ 847MITUpdated 4 days ago
Install
README from the maker
Open the README
Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.
Krewbill MCP
Krewbill gives each client a shared AI memory: a space of notes that a person has approved. Claude, ChatGPT and Cursor read those notes over a remote MCP server, so your team stops re-explaining a client's tone, rules and facts in every new chat.
Website: https://krewbill.com
This repository only describes the hosted Krewbill MCP service. The service itself is closed-source.
What it does
- One space per client, holding notes a person has approved.
- Assistants can read a space's approved notes.
- Assistants can only suggest new notes. Nothing is saved to the space until a person approves it.
- Each connection key is limited to the spaces you choose, can be read-only, and can be revoked.
- Accounts, workspaces, roles and invitations are available in the web app.
- Works with any MCP client that supports remote (HTTP) servers. Tested with Claude Code; use with other clients may need a different setup.
Tools
| Tool | What it does |
|---|---|
list_spaces | Lists the spaces your key may read. |
get_space_context | Returns a space's approved notes (voice and rules, key facts, decisions). Assistants call it first, before drafting for a client or project. |
search_memory | Searches approved notes by keyword, in one space or in all spaces your key can read. |
suggest_memory | Proposes a new note. It waits in an approval queue until a person approves it, and never changes shared memory by itself. |
flag_stale | Flags an approved note as possibly out of date for a person to review. It never edits or removes the note. |
A key can cover one space, several, or all of them, and can be read-only. Read-only keys cannot suggest notes.
Connect
- Create a space and a connection key at https://krewbill.com (see https://krewbill.com/connect).
- Krewbill shows your personal server address once, when you create the key. Copy it.
- Add it to your assistant. For Claude Code:
claude mcp add --transport http krewbill <your-server-address>If your tool asks for a header instead of a key in the address, use the plain server address https://www.krewbill.com/api/mcp and send Authorization: Bearer .
Create one key per tool, so you can revoke each separately.
Status
Krewbill is free during early access, until December 30, 2026. Connections authenticate with keys.
Feedback
https://krewbill.com/feedback