FusionMD

FusionMD uses AI for four things: generating or expanding content (draft a paragraph, write a section, continue where you left off); rewriting and polishing (adjust tone, improve clarity, make it shorter); explaining grammar — the Parts of Speech panel can ask AI to explain why a word functions as a particular part of speech in that specific sentence; and context-aware assistance — the AI knows whether you are writing Markdown, filling a template, or building a screenplay, and adapts its suggestions accordingly. AI is optional: every feature except AI generation works without any AI configuration.

Yes. When you set the document language — any of FusionMD's 40 supported languages — that language is passed to the AI on every generation request. Ask for a paragraph and the AI writes in the document's language with correct spelling conventions, vocabulary, and punctuation style. You never need to say "write in French" each time. This works with both Apple Intelligence and OpenRouter-connected models.

Yes. The Metadata panel lets you set the title, author, description, language, and cover image for your document. Export to ePub3 and those fields are embedded in the file exactly as ebook distributors expect. Markdown headings become chapter entries in the ePub's table of contents automatically. The document language travels into the ePub metadata and sets the correct reading direction — including right-to-left for Arabic and Hebrew. No third-party tools are required — FusionMD includes a built-in ePub3 exporter as well as a Pandoc-based alternative path for extended metadata control.

A Boilerplate is a reusable chunk of content — a paragraph, a section, a disclaimer, a signature block — that you have written once and want to insert repeatedly. Unlike a Template (which is a whole-document starting point), a Boilerplate is a piece you drop into any document mid-writing. Store your standard contract clause, your author bio, your product description — then insert it in one click from the Boilerplate panel. Boilerplates are stored on your Mac and work offline.

Use AI to generate multiple distinct content blocks — a headline, a product description, a pull quote, a caption — each as its own document or section with the appropriate paragraph style applied (Heading 1, Body, Pull Quote). When you export to IDML, FusionMD maps those style names into the IDML file. Open the IDML in Affinity or InDesign and the content arrives pre-tagged and ready to flow into your layout. You can generate, review, and refine the text entirely in FusionMD before the layout app ever opens.

Completely. The editor, templates, boilerplates, ePub3 export, IDML export, Fountain screenplay mode, the full Writing Coach (spell check, grammar, thesaurus, dictionary, proofreader, style analysis, and more), and the full 40-language system all work without any AI. You don't need an Apple Intelligence device, and you don't need an OpenRouter API key. AI is an optional layer on top of a fully functional writing and publishing tool.

A Template is a whole-document starting point — a blank form with {{variable}} placeholders, required fields, and conditional sections that you fill in to produce a complete document. A Boilerplate is a reusable passage you insert mid-document at any point. Think of Templates as forms and Boilerplates as a clipboard of pre-written content. You can use both in the same document: start from a template, then insert boilerplates to fill the variable sections.

FusionMD saves documents as .fusiondoc files. A .fusiondoc is a plain JSON file with your Markdown stored directly in a text field, alongside metadata like the document's language, theme, and variable values if the document was created from a template. You can open any .fusiondoc in a plain text editor and read your writing right there in the file. FusionMD also opens plain .md files directly, and File → Save As can export any document straight to .md. Templates are saved as .fusiontemplate files and work the same way.

No. FusionMD is a complete writing tool without either. IDML export is the publishing bridge for users who do page layout, but it is one feature of many. If you write blog posts, reports, screenplays, or template-driven documents and never open a layout tool, FusionMD is still the right tool.

iA Writer and Ulysses are excellent focused Markdown editors. FusionMD goes further in four ways. First, templates: {{variable}} placeholders, typed fields, required-field enforcement, and conditional sections — neither iA Writer nor Ulysses has anything close. Second, boilerplates: a managed library of reusable content blocks. Third, ePub3 export: publish an ebook directly from your document, with cover image, metadata, and correct chapter structure, no conversion required. Fourth, IDML export: hand a properly tagged document to Affinity or InDesign. FusionMD is priced identically to iA Writer and adds capabilities neither competitor ships.

No. FusionMD's spell check and grammar checking don't rely on the system-wide setting that Grammarly changes — the editor explicitly enables its own continuous spell checking regardless of that setting, and the Writing Coach's Spelling and Grammar tabs run their own checks independently. We tested this directly with Grammarly installed and active: both the inline red-underline spell check and the Writing Coach panel caught every misspelling correctly, with no suppressed results. Vocabulary, Proofreader, Style & Clarity, Parts of Speech, and Dialogue don't touch the system spell-check service at all, so they're unaffected regardless of what else is installed. You shouldn't see duplicate or conflicting suggestion overlays inside the FusionMD editor either, since Grammarly targets standard system text fields and FusionMD's editor is a custom view. One unrelated thing worth knowing: installing Grammarly's Mac app silently turns off macOS's own system-wide spell check (a Grammarly behavior, not FusionMD's), which is why spelling underlines can disappear in apps like Mail or Notes after installing it. If you want that back, Terminal: defaults write -g NSAllowContinuousSpellChecking -bool true — this has no effect on FusionMD either way, since it doesn't depend on that setting. There's also a language angle: Grammarly's own writing support covers roughly two dozen languages, and doesn't include Russian, Chinese, Arabic, Hebrew, Persian, Thai, Greek, or the three Celtic languages (Welsh, Irish, Scottish Gaelic). FusionMD's spell check, grammar analysis, and AI writing assistance handle all of these natively, as part of the same 40-language system — so if you write in one of them, FusionMD's Writing Coach isn't just unaffected by Grammarly, it's doing something Grammarly can't do at all.