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
Hjarni
Overview
Description from the maker (original English)
Markdown-based note-taking with a hosted MCP server. Your notes serve you and your AI.
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 checksi1 of 1 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
Install
Pick the AI app you use, then copy the settings.
Before you install
- Basic checks: 1 of 1 passed
- Runs on the maker’s server: what you ask it goes through their server.
- The registry lists no key to fill in.
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 …”.
Works in Claude on the web, desktop and mobile:
- Open Settings → Connectors
- Press Add custom connector
- Paste the address below and press Add
- If it asks you to sign in, sign in with the maker
https://hjarni.com/mcpRun this in your terminal
claude mcp add --transport http hjarni https://hjarni.com/mcpOr copy the settings yourself
Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"hjarni": {
"url": "https://hjarni.com/mcp"
}
}
}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": {
"hjarni": {
"type": "http",
"url": "https://hjarni.com/mcp"
}
}
}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.
ChatGPT connects only to servers on the internet:
- Open ChatGPT on the web → Settings → Connectors (Apps)
- Press Create or Add (some plans need Developer mode under Advanced first)
- Paste the address below, give it a name and save
- If it asks you to sign in, sign in with the maker
https://hjarni.com/mcpMenu names can differ slightly by plan and over time.
Your choice stays on this device in a cookie; no account needed.
These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.
What it can do
We have not read this server’s tool list yet; we check endpoints in rotation.
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 6, 2026
- ✓ Pass
Maker matches the repo
The registry name was verified against the domain hjarni.com (the registry checks domain ownership)
- … 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
- … Not checked yet
Endpoint responds
Not checked yet; we check endpoints in rotation
- … Not checked yet
Sign-in with OAuth
Not checked yet; we check endpoints in rotation
- … 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 2174 servers in this category
- Published to the registry more recently than 6% of the other 2174 servers in this category
- Basic checks equal to or better than 100% of the other 2174 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 Hjarni safe?
It passed 1 of 1 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?
The registry does not list a required key, though some servers ask you to sign in on first use.
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 (1.0.0) reached the registry 7 months 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 6 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 3 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.
Hjarni
Markdown notes for you, ChatGPT, and Claude.
An official, hosted MCP server for the same notes you read and edit.
Website · Docs · Blog
What it does
Hjarni is a Markdown note-taking app with an official, hosted MCP server at https://hjarni.com/mcp. Write and edit notes in the browser or Hjarni's iPhone, iPad, Apple Silicon Mac, and Android apps. Connect ChatGPT, Claude, or another compatible MCP client to search, read, create, update, and organize those same saved notes.
Use folders, tags, wiki-links, and instructions to keep a project brief, research notebook, or second brain current across assistants. You can review saved changes in note history, restore an earlier body, and export active notes as Markdown with attachments.
Hjarni hosts the server; connecting does not require running a local bridge or Docker container. This repository documents that hosted service. See client compatibility for setup routes and client-specific limits.
Keep client context between ChatGPT and Claude
Keep each client's preferences, agreed scope, dated decisions, current status, and next action in one project brief. ChatGPT and Claude can read and update that same Markdown note through Hjarni's official, hosted MCP server.
- Connect both assistants to the same Hjarni account using the setup guides below. Start with the Client Project Context template: it creates a project index and a blank brief to fill with facts you confirm. Keep a separate brief for each client and project.
- Before drafting, ask the assistant to find the correct client and project, read the full current brief, and return its source link. If several notes match, have it clarify which one to use.
- Draft proposed updates in chat first. After you confirm them, ask the assistant to save only those changes to the same brief, preserving other facts and the dates and reasons behind decisions. Open the note to check the result.
- In a fresh chat with the other assistant, explicitly ask it to retrieve that updated brief before continuing the work. Check that it reports the new status and next action alongside the unchanged scope and preferences.
Connecting makes saved notes available; it does not guarantee retrieval or copy every conversation or the assistants' native memories. The recorded client-context walkthrough shows both assistants using the same fictional brief, with prompts to repeat the checks.
Review, recover, and export
Note history and Trash let you inspect saved edits and their recorded author or AI client, compare a previous note body with the current text, and restore an earlier body as a new version. Restoring replaces the whole body, including any later edits; the current title, folder, and other fields stay unchanged. Rapid edits by the same author can be grouped into one revision. Deleted notes and folders remain recoverable in Trash for 30 days, subject to account limits. History reviews saved changes; approval before a write depends on the assistant's connection and settings.
Export and data ownership explains how to download active notes as a Markdown ZIP with folders and attachments, and includes a sample ZIP to inspect without an account. Export is an action in Hjarni, not an MCP tool. The standard Markdown ZIP excludes archived and trashed notes, revision history, and folder instructions; wiki links and attachment URLs may need updating in another app. Personal notes, individual folders, and teams can be exported separately.
Connect
The endpoint is https://hjarni.com/mcp. Use OAuth sign-in for ChatGPT and Claude; no manually copied API token is needed. For a client that accepts an Authorization header, Hjarni also supports full-access API tokens and restricted agent tokens.
Claude.ai / Claude Desktop / Claude mobile
Hjarni is in the Claude Connectors Directory: open the listing, click Connect, and sign in.
Or add it by URL:
- Open Customize > Connectors and add a custom web connector.
- Enter the URL
https://hjarni.com/mcp. - Choose OAuth sign-in, finish adding the connector, and sign in to Hjarni.
See the Hjarni Claude guide and Claude's current connector instructions for account and workspace requirements. Custom connectors are available on Claude Free, with a limit of one; Team and Enterprise owners manage workspace availability.
Claude Code
claude mcp add --transport http hjarni https://hjarni.com/mcpAdd --scope user to make it available in every project. Then run /mcp inside Claude Code to complete the OAuth sign-in.
ChatGPT
Install Hjarni from its ChatGPT directory page and sign in. See the ChatGPT setup guide for availability and usage.
If your account permits custom MCP servers, you can also add it by URL:
- Open Plugins, select +, then Add custom MCP server.
- Enter a name, the server URL
https://hjarni.com/mcp, and OAuth authentication. - Review the connection details, create and install the plugin, and sign in to Hjarni.
- In a new chat, select Hjarni from the
@menu and ask it to find a saved note.
Custom-server availability and workspace controls are separate from installing the directory entry. Follow OpenAI's current custom MCP instructions if the labels in your account differ.
Other MCP clients
Clients need Streamable HTTP and a supported authentication method: OAuth 2.0 with PKCE or Authorization: Bearer YOUR_API_TOKEN. OAuth discovery is at https://hjarni.com/.well-known/oauth-authorization-server; protected resource metadata is at https://hjarni.com/.well-known/oauth-protected-resource. Features such as prompts, panels, and events depend on the client.
Setup guides: Cursor · Copilot · Copilot Studio · Perplexity · Raycast
Access and agent tokens
OAuth sign-in connections use the access of the connected Hjarni account, including its authorized team and shared notes. Naming one folder in a prompt or adding folder instructions does not restrict that connection's access.
For compatible clients such as Claude Code or Cursor, create an agent token in Settings > Connections and grant no access, read, or write at a space or folder. Grants inherit down the tree and can be overridden below it; an agent cannot exceed your own access. Each token can have its own instructions and identity in history. Use the token as a Bearer credential instead of the regular OAuth connection.
Restricted tokens see a narrower tool list and cannot use account-wide management tools or the note panel. They still expose a few account-wide details, including your profile, and brain instructions unless disabled for that token; the agent-token reference lists the exact boundaries. Privacy and permissions explains account, team, and connection access.
Available tools
The table describes assistant-facing tools. Actual availability depends on the connection's permissions and the client's cached tool list; reconnect or refresh the server in the client after a server update.
| Tool | Description |
|---|---|
me | Connected profile, teams, note quota, and onboarding state; restricted tokens return their grants instead of account-wide quota and onboarding |
dashboard-get | Overview of the account: counts, recent notes, and recent changes across all spaces |
search | Full-text search across notes, containers, and tags |
notes-list | List notes with filtering by container, tags, and sorting |
notes-get | Read a single note: full body, tags, links, backlinks, files, and inherited AI instructions |
notes-create | Create a new note with title, body, summary, tags, and container placement |
notes-update | Edit or append content, replace or append a Markdown section, move notes, change tags, archive, favorite, or mark verified |
notes-open | Open an editable note panel on supported hosts, or return note data on other clients; omit the ID to open a picker |
notes-delete | Move a note to Trash (recoverable for 30 days) |
notes-restore | Restore a note from Trash |
notes-history | Read a note's revision history: who wrote each version, when, and what changed |
notes-revert | Revert a note's body to an earlier revision (appends a new revision, so it can be undone) |
containers-list | List folders for organizing notes |
containers-get | Get a single container with its description and AI instructions |
containers-create | Create new folders |
containers-update | Update a container (rename, move, change description, archive) |
containers-permissions | Set or clear a team member's role on a team container |
containers-delete | Move a folder, its sub-folders, and their notes to Trash (recoverable for 30 days) |
containers-restore | Restore a deleted folder and everything deleted with it |
tags-list | List all tags |
tags-create | Create new tags |
tags-manage | Rename, merge, or delete a tag |
links-manage | Create or remove bidirectional links between notes |
instructions-get | Read AI instructions at brain, personal root, container, or team level |
instructions-update | Replace or append brain, personal-root, personal-folder, or team instructions, subject to access and owner permissions |
files-attach | Attach a base64 file to a personal note |
files-attach_from_url | Attach a public URL or native ChatGPT file reference to a personal note |
files-create_upload_url | Generate a one-time browser upload link for an authorized personal, team, or shared note |
files-check_upload | Check the status of an upload link |
files-get_download_url | Get a temporary, login-free download URL; treat it as a credential while valid |
files-remove | Permanently remove an attachment from a personal note |
email-addresses-list | List email capture addresses |
email-addresses-create | Create an email capture address: mail sent to it becomes a note, subject to account eligibility |
teams-list | List all teams the user is a member of |
teams-get | Get team details including recent notes |
teams-create | Create a new team |
teams-invite | Invite a teammate by email or get a shareable join link |
feedback-submit | Send feedback about Hjarni to the maintainers |
nudges-dismiss | Dismiss a product suggestion the user declined |
For edits, read the current note first and prefer targeted
Only the beginning is shown; read the rest in the repo