Using slim.to with Claude

Two ways to let Claude create slim.to links from the artifacts and files it produces: the MCP server (best — native tools) or the REST API (no setup beyond an API key).

Prerequisite for both: a personal API key.

Approach 1 — MCP server

Claude Code (CLI)

One command:

claude mcp add slimto \
  --env SLIMTO_API_KEY=slim_your_key_here \
  -- uvx --from /path/to/slimto/mcp slimto-mcp

Then in any session:

You: Write up the Q3 numbers as a PDF and give me a slim.to link for it.

Claude: (writes the PDF, calls create_link_from_file) Done — https://slim.to/4h7bqn. I can check who's opened it whenever you ask.

Scope the server to one project with claude mcp add --scope project … (writes .mcp.json in the repo) or make it available everywhere with --scope user.

Claude Desktop

Add the server to claude_desktop_config.json (Settings → Developer → Edit Config):

{
  "mcpServers": {
    "slimto": {
      "command": "uvx",
      "args": ["--from", "/path/to/slimto/mcp", "slimto-mcp"],
      "env": {
        "SLIMTO_API_KEY": "slim_your_key_here"
      }
    }
  }
}

Restart Claude Desktop; the slimto tools appear under the tools icon. Because the server runs on your machine, Claude Desktop can upload any local file it can see — including files it just created.

claude.ai (web) / mobile — hosted connector

slim.to ships a hosted remote MCP server, so no install is needed:

1. On claude.ai: Settings → Connectors → Add custom connector.
2. Enter the URL https://slim.to/mcp.
3. Claude opens the slim.to sign-in/consent page — click Authorize.

That's it. Claude on web and mobile can now shorten URLs, publish the HTML pages it writes as tracked links (create_link_from_content), update an already-shared link in place (replace_link_content — same URL, analytics intact), delete links, list your links, and answer "did anyone open it?" from your analytics. Revoke access anytime from Dashboard → Settings → Connected apps.

Large files. Content sent inline has to be generated token-by-token by Claude, which is slow for big files and can be cut short by tool-call size limits. slim.to handles this three ways:

• source_url — slim.to downloads the content itself. By far the fastest path, but the URL must be publicly readable; slim.to fetches it as an anonymous visitor, so private links won't work.
• Chunked upload (start_content_upload) — for content Claude is writing itself. This guarantees the file arrives whole; it does not make it quicker, since Claude still has to write every byte.
• sha256 / expected_bytes — an integrity check, so a truncated upload is rejected instead of published broken. Only pass values computed with a code tool; a guessed digest will always fail the check.

Note the remote server's upload tool takes content rather than a file path (hosted Claude has no access to your disk) — for uploading arbitrary local files, Claude Desktop/Code with the local server is the better fit.

Approach 2 — REST API (no MCP)

Claude Code can drive the API with plain curl — handy when you don't want to install anything. Put the key in your shell env (~/.zshrc):

export SLIMTO_API_KEY=slim_your_key_here

Then ask Claude Code:

Upload ./report.pdf to slim.to and give me the short link. Use POST https://slim.to/api/v1/files with the X-API-Key header from $SLIMTO_API_KEY, sending the file as multipart field file.

Or teach it once by adding a note to your project's CLAUDE.md:

## Sharing deliverables
When I ask for a shareable link for a file, upload it to slim.to:
`curl -s -X POST https://slim.to/api/v1/files -H "X-API-Key: $SLIMTO_API_KEY" -F "file=@<path>" -F "title=<title>"`
and give me the `link.short_url` from the response.

The full endpoint reference is in the API quickstart.

Which approach?

Use MCP where you can; REST is the universal fallback.