# An agent writes it. You still have to understand it. An AI agent can draft a plan, a spec or a set of notes quickly. What it produces still has to be understood by the person who acts on it — not trusted because it reads fluently. **MarsDawn is built for that read: the rendered page next to the source, with Mermaid diagrams and KaTeX math drawn out instead of left as marks, so a document's structure is legible at a glance.** ## Fluent isn't the same as correct Writing about AI-assisted coding, Simon Willison put it this way about code that will be worked on again, not thrown away: “the quality and understandability of the underlying code is crucial” ([Vibe coding](https://simonwillison.net/2025/Mar/6/vibe-coding/), 2025). The same holds for a document: an agent's draft that reads smoothly can still get the structure, the numbers or the logic wrong, and fluent prose doesn't announce which parts to check. ## Inference, not compilation Birgitta Böckeler, writing for Thoughtworks, draws the distinction plainly: “LLMs are NOT compilers, interpreters, transpilers or assemblers of natural language, they are inferrers” ([I still care about the code](https://martinfowler.com/articles/exploring-gen-ai/i-still-care-about-the-code.html)). A compiler either accepts your input or reports an error; an agent can hand back something that runs, or reads, without being right. Somebody still has to check it. ## What MarsDawn gives that reader - The rendered page next to the source, updating as either side changes, so a claim in the text and the way it's structured are both in view at once. - Mermaid diagrams drawn out: a flowchart an agent described in text becomes a shape you can actually follow. - KaTeX math rendered, not left as a string of backslashes: a formula reads as a formula. - Nothing runs on its own. MarsDawn doesn't grade, summarize or flag the document for you — it puts the structure in front of you so you can. ## Next - How that review stays cheap for the agent's own context: [token-efficient review](/token-efficient-review/). - Handing the reviewed document to someone else: [sharing a PDF](/sharing-exported-pdfs/). - What MarsDawn is, in one page: [the home page](/). ## More - [MarsDawn](https://marsdawn.southern-light.dev/index.md): A native Mac Markdown editor with live preview, Mermaid diagrams and PDF export, built for reading what AI agents write. Coming soon to the Mac App Store. - [Your writing stays on your Mac](https://marsdawn.southern-light.dev/yours/index.md): MarsDawn has no account, no sync and no cloud. Your Markdown documents stay on your Mac, in the files and folders you choose. - [Try free, pay once](https://marsdawn.southern-light.dev/pay-once/index.md): MarsDawn is free to download. Try everything for 14 days, then unlock it once for USD 4.99. No subscription, no account. - [PDF export](https://marsdawn.southern-light.dev/pdf/index.md): Export Markdown as a PDF or print it on your Mac, with Mermaid diagrams and highlighted code. Page breaks avoid splitting short code blocks and tables. - [A Mac app](https://marsdawn.southern-light.dev/native/index.md): A Markdown editor that is a real Mac app: native windows and tabs, autosave, version history, Quick Look in Finder and a text editor that behaves like a Mac. - [What MarsDawn doesn't do](https://marsdawn.southern-light.dev/limits/index.md): No sync, no iPhone or iPad app, no plugins, no accounts. Four built-in themes. Know before you buy. - [Support](https://marsdawn.southern-light.dev/support/index.md): Get help with MarsDawn, the Markdown editor for macOS. - [Privacy Policy](https://marsdawn.southern-light.dev/privacy/index.md): MarsDawn does not collect personal data. Your documents and settings stay on your Mac. - [View Markdown on a Mac](https://marsdawn.southern-light.dev/view-markdown-on-mac/index.md): A .md file is plain text with formatting marks in it. Here is how to read it rendered on a Mac: as a PDF with the free marsdawn command-line tool today, and in the MarsDawn app, coming soon to the Mac App Store. - [Markdown to PDF](https://marsdawn.southern-light.dev/markdown-to-pdf/index.md): Convert Markdown to PDF on a Mac with the free marsdawn command-line tool. Install it with Homebrew and run one command: tables, math, Mermaid and code. - [MacMD Viewer vs. MarsDawn](https://marsdawn.southern-light.dev/vs/macmd-viewer/index.md): MacMD Viewer renders Markdown read-only for USD 19.99. MarsDawn edits and previews side by side, free to try then USD 4.99 once on the Mac App Store. - [Command Line](https://marsdawn.southern-light.dev/cli/index.md): The free marsdawn command-line tool for Mac: export Markdown to PDF from a shell, a script or an LLM agent, with JSON output. Install it with Homebrew. - [marsdawn for agents](https://marsdawn.southern-light.dev/cli/agents/index.md): A reference for AI agents and scripts that call marsdawn to turn Markdown into PDF: commands, JSON output, schemas, exit codes and requirements. - [Agent skill](https://marsdawn.southern-light.dev/cli/skill/index.md): One file your coding agent loads to install marsdawn, check it works, export Markdown to PDF and read the JSON result. - [MCP server](https://marsdawn.southern-light.dev/cli/mcp/index.md): marsdawn has no AI model of its own, so it doesn't matter which agent wrote the Markdown. Call it from the CLI, a skill file, or the marsdawn-mcp MCP server: all three run the same export. - [Token-efficient review](https://marsdawn.southern-light.dev/token-efficient-review/index.md): A person reviews the rendered page in MarsDawn, never read back into the agent's context. The tool call itself returns a compact JSON result, not the rendered content, so calling it is cheap too. - [Viewing Markdown elsewhere vs. MarsDawn](https://marsdawn.southern-light.dev/vs/markdown-preview-tools/index.md): How MarsDawn compares to reading Markdown in VS Code's built-in preview, a browser extension, or Claude Desktop's file preview: what each renders, and what it takes to open one file. - [Preview themes and PDF export](https://marsdawn.southern-light.dev/themes/index.md): Four preview themes, each with a light and dark palette, and one PDF/print export that matches whichever you're in. More importable themes, and a gallery to share your own, are planned. - [Sharing exported PDFs](https://marsdawn.southern-light.dev/sharing-exported-pdfs/index.md): Export an agent's Markdown to PDF and hand it to a colleague who doesn't read Markdown and won't install anything. No syntax, no app and no account needed to open it. - [繁體中文](https://marsdawn.southern-light.dev/zh-hant/reviewing-ai-output/index.md): AI 寫的 Markdown 還是得由人來理解，不能因為讀起來通順就直接相信。MarsDawn 把排版後的頁面和原始碼並排，也把 Mermaid 圖表與 KaTeX 數學式畫出來，讓結構一眼就看得懂。 - [简体中文](https://marsdawn.southern-light.dev/zh-hans/reviewing-ai-output/index.md): AI 写的 Markdown 还是得由人来理解，不能因为读起来通顺就直接相信。MarsDawn 把排版后的页面和源代码并排，也把 Mermaid 图表与 KaTeX 数学式画出来，让结构一眼就看得懂。 - [日本語](https://marsdawn.southern-light.dev/ja/reviewing-ai-output/index.md): AI が書いた Markdown も、結局は人が理解しなければなりません。読みやすいからといって鵜呑みにはできません。MarsDawn はレンダリングされたページとソースを並べ、Mermaid 図と KaTeX 数式を描画するので、構造が一目で分かります。