Basecamp MCP Server

An MCP server for Basecamp 3. It lets MCP-capable clients such as Codex, Cursor, and Claude Desktop read and manage Basecamp projects through OAuth-authenticated Basecamp API calls.

The main server is basecamp_fastmcp.py. It uses the official mcp.server.fastmcp Python SDK and exposes 79 tools covering projects, todos, message boards, campfires, card tables, inbox forwards, documents, uploads, comments, events, webhooks, and search.

What It Can Do

• Browse Basecamp projects and project details.
• Search across projects, todos, messages, campfire lines, comments, uploads, and schedules.
• Read and manage todolists, todos, todo groups, and completion state.
• Read and create message board messages, including drafts and categories.
• Read campfire lines.
• Read and create comments.
• Work with card tables, columns, cards, and card steps.
• Read inbox forwards and replies.
• Read daily check-ins and answers.
• Upload attachments and inspect uploads.
• Read and manage documents, including drafts.
• List events and manage webhooks.
• Generate local MCP configuration for Codex, Cursor, and Claude Desktop.

Requirements

• Python 3.10 or newer.
• A Basecamp 3 account.
• A Basecamp OAuth application from https://launchpad.37signals.com/integrations.
• A client that can run local MCP servers, such as Codex, Cursor, or Claude Desktop.

If your system Python is older, use uv; it can create a virtual environment with a newer Python version.

Quick Start

Clone the repository and install dependencies:

git clone https://github.com/georgeantonopoulos/Basecamp-MCP-Server.git
cd Basecamp-MCP-Server

uv venv --python 3.12 venv
source venv/bin/activate
uv pip install -r requirements.txt

Or, if python already points to Python 3.10 or newer:

python setup.py

Create a .env file from the example and fill in your Basecamp OAuth details:

cp .env.example .env

Required values:

BASECAMP_CLIENT_ID=your-client-id
BASECAMP_CLIENT_SECRET=your-client-secret
BASECAMP_ACCOUNT_ID=your-account-id
USER_AGENT="Your App Name ([email protected])"

Authenticate with Basecamp:

python oauth_app.py

Open http://localhost:8000 and complete the OAuth flow. The token is stored locally in oauth_tokens.json by default.

Configure Your MCP Client

Codex

python generate_codex_config.py
codex mcp get basecamp

Useful options:

python generate_codex_config.py --dry-run
python generate_codex_config.py --legacy

The script writes a basecamp server entry to ~/.codex/config.toml and points it at this checkout's virtual environment and basecamp_fastmcp.py.

Cursor

python generate_cursor_config.py

Then restart Cursor and check Settings -> MCP. The server should appear as basecamp.

Claude Desktop

python generate_claude_desktop_config.py

Then fully quit and reopen Claude Desktop. The generated config is written to:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: ~/AppData/Roaming/Claude/claude_desktop_config.json
• Linux: ~/.config/claude-desktop/claude_desktop_config.json

Verify The Server

Run the FastMCP server through stdio and ask for its tool list:

printf '%s\n%s\n%s\n' \
  '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-06-18","capabilities":{},"clientInfo":{"name":"test","version":"1.0"}}}' \
  '{"jsonrpc":"2.0","method":"notifications/initialized","params":{}}' \
  '{"jsonrpc":"2.0","id":2,"method":"tools/list","params":{}}' \
  | python basecamp_fastmcp.py

Run the automated tests:

python -m pytest tests/ -v

Available Tools

The FastMCP server exposes 79 tools.

Projects And Search

• get_projects
• get_project
• search_basecamp
• global_search

Todos

• get_todolists
• get_todolist
• create_todolist
• update_todolist
• trash_todolist
• get_todos
• get_todo
• create_todo
• update_todo
• delete_todo
• archive_todo
• complete_todo
• uncomplete_todo
• reposition_todo
• get_todolist_groups
• create_todolist_group
• reposition_todolist_group

Messages, Campfires, And Check-Ins

• get_message_board
• get_messages
• get_message
• get_message_categories
• create_message
• create_draft_message

Pass publish: false to create_message to create a draft message instead of posting it immediately. Agents can also call create_draft_message directly when the intended operation is specifically to create a draft.

• get_campfire_lines
• get_daily_check_ins
• get_question_answers

Comments

• get_comments
• create_comment

Card Tables

• get_card_tables
• get_card_table
• get_columns
• get_column
• create_column
• update_column
• move_column
• update_column_color
• put_column_on_hold
• remove_column_hold
• watch_column
• unwatch_column
• get_cards
• get_card
• create_card
• update_card
• move_card
• complete_card
• uncomplete_card
• get_card_steps
• create_card_step
• get_card_step
• update_card_step
• delete_card_step
• complete_card_step
• uncomplete_card_step

Inbox Forwards

• get_inbox
• get_forwards
• get_forward
• get_inbox_replies
• get_inbox_reply
• trash_forward

Documents, Uploads, Attachments, Events, And Webhooks

• create_attachment
• get_uploads
• get_upload
• download_upload — download a vault Upload recording (Docs & Files) and return its bytes as MCP content (ImageContent for image MIME types, EmbeddedResource / BlobResourceContents otherwise). The MCP host forwards the blob to the model, so PDFs, images, and documents are read natively without an out-of-band fetch.
• download_attachment — download an inline comment/message attachment by its content_attachments[].download_url and return it as MCP content. Use this for files embedded into a comment or message body. Inline attachments are Attachment objects with their own IDs and cannot be resolved through /uploads/{id} — that endpoint returns 404. For files that are their own Upload recording in a vault, use download_upload instead.

Host compatibility for download_upload and download_attachment. Both tools return MCP content blocks. The file is only readable by the model if the MCP host forwards ImageContent / EmbeddedResource (BlobResourceContents) on. Status as of June 2026:

• Claude Code (CLI) — fully supported, including application/pdf and other binary blob resources.
• Claude Desktop / claude.ai web — image content blocks work, but non-image EmbeddedResource blocks are rejected with "Resources of type 'application/pdf' are not currently supported". The bytes reach the host but never the model. Once the client adds support, these tools become useful in those frontends without server changes.
• get_documents
• get_document
• create_document
• create_draft_document

Pass publish: false to create_document to create a draft document instead of publishing it immediately. Agents can also call create_draft_document directly when the intended operation is specifically to create a draft.

• update_document
• trash_document
• get_events
• get_webhooks
• create_webhook
• delete_webhook

Example Prompts

• "Show me all my Basecamp projects."
• "Search Basecamp for deadline."
• "Get the todolists for project 123456."
• "Create a todo called Review PR in todolist 987654."
• "Show me the message board categories for project 123456."
• "Post an Announcement to the project message board."
• "Show me the card table columns for project 123456."
• "Move this card to the Done column."
• "List the latest uploads in this project's vault."
• "Download the screenshot attached to that comment so you can read it."

Architecture

• basecamp_fastmcp.py: FastMCP stdio server used by MCP clients.
• basecamp_client.py: Synchronous Basecamp 3 API client.
• search_utils.py: Higher-level search helpers across Basecamp resources.
• oauth_app.py: Local Flask OAuth flow for Basecamp authentication.
• auth_manager.py: OAuth refresh helper used before API calls.
• token_storage.py: Local OAuth token storage.
• generate_codex_config.py: Codex MCP configuration generator.
• generate_cursor_config.py: Cursor MCP configuration generator.
• generate_claude_desktop_config.py: Claude Desktop configuration generator.
• mcp_server_cli.py: Legacy JSON-RPC server kept for compatibility and tests.

Authentication And Token Storage

The recommended path is OAuth 2.0:

1. Create a Basecamp OAuth app.
2. Put the client ID, client secret, account ID, redirect URI, and user agent in .env.
3. Run python oauth_app.py.
4. Complete the browser flow at http://localhost:8000.

By default, OAuth tokens are stored in <project>/oauth_tokens.json. For containers, read-only checkouts, or mounted token volumes, set BASECAMP_MCP_TOKEN_FILE:

export BASECAMP_MCP_TOKEN_FILE=/var/lib/basecamp-mcp/oauth_tokens.json

Both the OAuth app and the MCP server read the same variable. token_storage.py expands ~ and environment variables in this path, creates the parent directory if needed, and attempts to set the token file permissions to 0o600 when writing. Parent directory permissions are still your responsibility.

Troubleshooting

If tools do not appear in your MCP client:

1. Confirm the virtual environment exists and has the MCP SDK:

   ./venv/bin/python -c "import mcp; print('MCP available')"

2. Confirm .env contains BASECAMP_ACCOUNT_ID.

3. Re-run the relevant config generator.

4. Fully quit and restart your MCP client.

If authentication fails:

python oauth_app.py

Then open http://localhost:8000 and complete the Basecamp OAuth flow again.

For Claude Desktop on macOS, MCP logs are usually under:

~/Library/Logs/Claude/

Security Notes

• Do not commit .env or oauth_tokens.json.
• Use a descriptive USER_AGENT that includes contact information, as Basecamp expects API clients to identify themselves.
• Keep token files on local or appropriately permissioned storage.
• This server is designed for local MCP client use. Review the code and deployment model before exposing it on a network.

License

MIT. See LICENSE.

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