PostMD MCP Server
stdio Model Context Protocol server for PostMD — publish a Markdown document, get a web page you share by link. Optional groups, document passwords, share expiry and viewer themes. This server wraps PostMD's public API (/api/v1) so assistants can publish, read, update and organize documents.
Publishing needs no account and no key. With zero configuration this server can already turn Markdown into a shareable page. An API key adds management: updating and deleting your documents, attachments, and groups.
Anonymous documents come with a control token. Publishing without a key returns data.controlToken and data.retainedUntil: the document is deleted at that instant, and the token is the only way to update or delete it before then. It is shown once and cannot be reissued, so keep it with the docCode. Pass it as controlToken to the update and delete tools and they work without an API key.
HTTP reference: postmd.turink.com/docs/api · machine-readable spec at /api-docs
Requirements
- Node.js 20 or later
- Nothing else. An API key (
pmk_…) only for the management tools.
Configuration
All variables are optional.
| Variable | Description |
|---|
POSTMD_BASE_URL | Defaults to https://postmd.turink.com. Set for a self-hosted / local instance. Origin only, no trailing slash. |
POSTMD_API_KEY | pmk_… for the tools marked with a scope below. Sign in at postmd.turink.com, open Account → API keys, pick the scopes you need — read and write are independent, and a 403 usually means a missing scope. |
POSTMD_DEBUG | 1 / true / yes → extra stderr logging. |
Load order: this repo's .env (if present) is applied via dotenv without overwriting variables already set by the host (e.g. MCP env). Do not commit .env or keys.
Publishing and reading — no key needed:
| Tool | Purpose |
|---|
postmd_create_document | Publish Markdown, get docCode + share URL |
postmd_create_document_from_file | Same, but this server reads a local filePath (large files) |
postmd_get_document | Metadata by docCode |
postmd_get_document_raw | Stored Markdown body (optional password) |
Managing documents — key with documents:write:
Each of the first three also accepts controlToken instead of a key, for a document published anonymously.
| Tool | Purpose |
|---|
postmd_update_document | Replace content and/or metadata; can clear password / end date |
postmd_update_document_from_file | Same, body read from a local filePath |
postmd_delete_document | Delete a document (no undo) |
postmd_upload_attachment | Upload an image/PDF, get a URL to embed in Markdown |
postmd_create_documents_from_files | Bulk-publish several .md files in one call |
postmd_move_document_to_group | Move a document into a group / folder |
Replacing content on a document that has notes
Notes are located by the text they quote, not by a stored position. Replacing a
document's body therefore moves or loses where they point: a note whose quote is
gone loses its place in the body, and one whose quote now appears elsewhere points
there instead. The note itself, including the quoted text, is kept either way.
Both update tools require notesOnReplace whenever new content is sent.
| Value | Effect |
|---|
keep | Replaces the content and leaves the notes as they are |
abort | Refuses when the document has notes anchored to its text, and says how many |
Metadata-only updates do not take it.
Notes and highlights — key with documents:read / documents:write. A note is
text anchored to a quoted passage; a highlight is the same object carrying only
a colour. Visibility comes from ownership: on the key member's own document a note
is PRIVATE or SHARED, and on anyone else's document it is always SHARED.
Documents nobody owns — anonymous uploads and service-owned pages — take no notes:
| Tool | Purpose |
|---|
postmd_list_notes | Notes on a document: yours + every SHARED one |
postmd_add_note | Attach a note, or a colour-only highlight to a quoted passage |
postmd_update_note | Edit a note you wrote |
postmd_resolve_note | Mark a SHARED discussion settled, or reopen it |
postmd_delete_note | Delete yours, or a SHARED note on your document |
postmd_list_my_notes | Your notes across every document |
Groups — key with groups:read / groups:write:
| Tool | Purpose |
|---|
postmd_list_groups | Groups visible to the key (paged) |
postmd_list_group_documents | Documents in a group (paged, searchable, sortable) |
postmd_create_group | New group |
postmd_update_group | Rename / change expiry |
postmd_delete_group | Delete a group (documents survive) |
For uploads: either pass the full Markdown as the markdown argument, or pass a local filePath only so this server reads the file. The path must exist on the machine running the MCP server.
Quickstart
Nothing to install. npx fetches the package and the MCP client spawns it.
Run it by hand only to check that it starts — it speaks MCP over stdin and stdout, so it
will sit there waiting for a client.
Client configuration
Claude Code:
claude mcp add postmd -- npx -y postmd-mcp-server
Cursor (~/.cursor/mcp.json) and most other stdio clients:
{
"mcpServers": {
"PostMD": {
"type": "stdio",
"command": "npx",
"args": ["-y", "postmd-mcp-server"],
"env": { "POSTMD_API_KEY": "pmk_…" }
}
}
}
To run a checkout instead — changing the code, or debugging against a local PostMD —
point the client at the file.
git clone https://github.com/reinlainer/postmd-mcp-server.git
cd postmd-mcp-server && npm ci
claude mcp add postmd-dev -- node "$PWD/src/index.js"
Leave env out entirely for publish/read-only use. cp .env.example .env works too — the server loads its own .env.
Smoke test
Runs the full write path against a live server and cleans up after itself. Needs a key with all four scopes.
export POSTMD_API_KEY=pmk_…
npm run smoke
Creates a group and a passworded document, reads it back, updates it, clears the password, then deletes both. It also publishes one document with no credential and removes it with the control token.
Stack
@modelcontextprotocol/sdk 1.30.0, dotenv. License: MIT.