monthletHow monthlet tests AI responses (eval)
monthlet writes and edits notes through AI tool calls. This is a look at the scoring harness we added for those calls in August, and more importantly at what it does not measure.
Blog
Posts about building monthlet. Written in Japanese first, then translated here.
Putting charts inside a note
monthlet renders charts as blocks inside a note. Ask in chat and the chart is placed in the note, optionally linked to a spreadsheet range so it recalculates when the sheet changes.
Editing Notes Together with AI
monthlet lets you write notes through AI chat and then edit them by hand. This article explains the three editing modes that make both kinds of editing possible in a single note.
Deciding how a note looks with themes
monthlet separates a note's structure from its appearance. Blocks carry meaning, and a theme decides how that meaning is displayed — across presets, folders, individual notes, and exported HTML.
Turning frequent instructions into skills
Skills let you save instructions you send to the AI repeatedly and call them up from the chat input with a slash command, including variables for the parts that change.
Managing notes with tags
How tags work in monthlet — adding them by hand or from AI suggestions, filtering notes by tag, renaming or deleting tags in bulk, and how tag colors feed the note map.
One Month After Release and the Road Ahead
A look back at monthlet's first month since the beta release, the numbers behind it, and the product roadmap through 2027.
The architecture of monthlet
How monthlet is built internally — the three layers inside a single note file, the process split in the app, and the options that were ruled out to keep every note a single .html file.
Reusable note templates
Version 0.16.0 ships with two note templates, Meeting notes and Weekly review. Ask in chat, and the AI builds a note on top of the template structure.
Note links and the note map
monthlet lets you link one note to another, and a new note map view draws those links as a graph so you can see how a vault is connected. Available from 0.16.0.
Connecting Google Calendar
From version 0.14.0, monthlet can read and create Google Calendar events. Imported events become notes rather than entries in monthlet's calendar view.
Connecting to Google Sheets
From version 0.12.2, monthlet can read Google Sheets — either by asking about a sheet directly in Chat, or by importing sheets into a monthlet spreadsheet document.
monthlet is now an MCP server - read and write notes from external AI agents
Version 0.13.1 turns monthlet itself into an MCP server, so agents outside the app can read and write the notes in your vault through monthlet rather than touching the files directly.
monthlet now supports MCP — connecting external MCP servers
monthlet can now connect to MCP servers you register yourself, so you decide which external tools the AI in chat can use. This post walks through setup, confirmation prompts, lifecycle, and known limitations.
If You Are Not Sure How Something Works, Ask the AI — How Help Works in monthlet
monthlet ships a built-in help page and lets you ask usage questions directly in the AI chat, which answers from knowledge data bundled with the app. Version 0.12.0 also adds a way to report a chat response that did not work.
Syncing your vault with cloud storage
Because a monthlet vault is a plain folder of HTML files, you can keep it in sync across Macs with the cloud storage you already use. Here is how to set it up and what to watch out for.
Note history, and what comes next
Notes and spreadsheets now keep their earlier states, so you can go back to any of them — plus what is planned after this.
Introducing monthlet, an AI note-taking app
The first post — what monthlet does, why it is being built, and where the name comes from.