search_templatesReadsSearches the published template catalogue.
Catalogue only. No project data is touched.
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LetX · Model Context Protocol
Connect an AI client to a LetX project.
The hosted MCP endpoint provides named tools for templates, projects, text files, and LaTeX compilation. OAuth 2.1 controls access.
Open the official MCP guideHosted endpoint
https://api.letx.app/mcpUse the URL exactly as published. Authentication opens through OAuth; do not paste a LetX password or access token into a client.
Tool surface
Thirteen tools, six of which can write.
Five tools only read, six can change a project or spend compile quota, and two search the public template catalogue for ChatGPT deep research. The consequence column is what to weigh before approving a consent screen. Checked on September 27, 2026.
get_templateReadsReturns one template’s details, licence, and preview.
Catalogue only.
list_projectsReadsLists the projects on the connected account.
Reveals project names to the client.
list_project_filesReadsLists a project’s files and assets with exact paths.
Reveals file structure to the client.
read_project_fileReadsReads one text file from a project.
Sends document contents to the client.
create_project_from_templateWritesCreates a new project from a template.
Adds a project. Does not alter existing ones.
create_projectWritesCreates a project from supplied LaTeX source.
Adds a project. Does not alter existing ones.
update_project_fileWritesCreates or replaces a text file in a project.
Overwrites document content. The prior version stays in LetX history.
compile_latexWritesCompiles loose source to PDF.
Consumes the account’s compile quota.
compile_projectWritesCompiles a stored project and returns the PDF or the error log.
Consumes the account’s compile quota.
set_project_compilerWritesSwitches between pdfLaTeX, XeLaTeX, and LuaLaTeX.
Changes a project setting that affects future builds.
searchCatalogueDeep-research search across templates.
Catalogue only. Provided for ChatGPT deep research.
fetchCatalogueRetrieves a full template record by id.
Catalogue only. Provided for ChatGPT deep research.
Connect
Add the hosted endpoint to Claude, ChatGPT, Claude Code, or another compatible OAuth client.
Authorize
Sign in to LetX, inspect the requested scopes, and approve the connection.
Work
Ask the client to find a template, create a project, edit files, or compile. Open the resulting project in LetX for visual review and collaboration.
Security
Access controls.
OAuth 2.1
The external client does not receive the user’s LetX password.
Disclosed scopes
The consent step shows whether the client is requesting read or write access.
Revocation
The user can revoke a connection.
Project history
Prior file versions remain available according to the account’s history plan.
Text files
The documented tools edit project text files. Images and figures are uploaded through the editor.
Questions
Questions and answers.
What is the LetX MCP endpoint?
The hosted endpoint is https://api.letx.app/mcp. Compatible clients connect through OAuth 2.1.
Which clients does LetX test?
The published setup guide documents Claude, ChatGPT, and Claude Code.
Does an MCP client receive my LetX password?
No. OAuth authorization grants disclosed scopes without exposing the user’s password to the client.
Is the connection free?
Connecting is free, but MCP access is a Pro plan feature, and tool use follows the connected account’s quota and plan limits.
What can an authorised client actually change?
Six of the thirteen tools write: they can create projects, replace the contents of a project file, change the compiler, and consume compile quota. Five only read, and two search the public template catalogue. A replaced file leaves the previous version recoverable in LetX history.
Can access be revoked?
Yes. Authorisation is an OAuth grant against the LetX account, so a connected client can be revoked without changing the account password.
Primary sources
Product behavior and plan details were checked September 27, 2026. Verify the official LetX pages before making a purchase or security decision.