MCP stdio Implementation:
The PR adds support for standard input/output (stdio) as a transport
mechanism for the Message Control Protocol. This is a replacement to the
SSE (Server-Sent Events) transport that was worked on in PR #359 but
will not be merged as it's not deprecated.
This will allow developers to use Arcade tools (written by the dev or
Arcade) in Claude, Cursor, windsurf, etc.
The engine Gateway already supports adding HTTPS streamable (replacement
for SSE) MCP servers as tool servers, and will soon support full gateway
capability in the client API as well.
To use any existing Toolkit just
## Examples
### Quickstart setup with existing toolkits
```bash
pip install arcade-ai
pip install <name of toolkit> # ex. arcade-google
arcade serve --mcp
```
### Run with Claude
Just add the following to the Claude config
```json
{
"mcpServers": {
"arcade": {
"command": "bash",
"args": ["-c", "export ARCADE_API_KEY=arc_xxxx && /path/to/python /path/to/arcade serve --mcp"]
}
}
}
```
### Customizing the Tool Server
Developers can customize their served tools and server furthermore by
importing the worker sdk
```python
import arcade_google # pip install arcade_google
import arcade_search # pip install arcade_search
from arcade.core.catalog import ToolCatalog
from arcade.worker.mcp.stdio import StdioServer
# 2. Create and populate the tool catalog
catalog = ToolCatalog()
catalog.add_module(arcade_google) # Registers all tools in the package
catalog.add_module(arcade_search)
# 3. Main entrypoint
async def main():
# Create the worker with the tool catalog
worker = StdioServer(catalog)
# Run the worker
await worker.run()
if __name__ == "__main__":
import asyncio
asyncio.run(main())
```
Then to run with claude, just run this python file instead of the prebuilt server used in ``arcade serve --mcp``
## PR Description
This PR adds 7 examples.
* `call_a_tool_directly_with_auth.py` - Simple example that uses Arcade
client to execute a tool that lists Gmail emails
* `call_a_tool_directly.py` - Simple example that uses Arcade client to
execute a tool that adds two numbers together
* `call_a_tool_with_llm.py` - Simple example that uses the LLM api to
star the arcade-ai repository
* `get_auth_token.py` - Simple example that gets a Google auth token and
then calls the Google API
* `call_multiple_tools_directly_with_auth.py` - A more involved example
that directly calls multiple spotify tools sequentially
* `call_multiple_tools_with_llm.py` - A more involved example that uses
an llm to call multiple spotify tools sequentially
* `simple_chatbot.py` - Simple chatbot that uses arcade tools and has
history
---------
Co-authored-by: Nate Barbettini <nathanaelb@gmail.com>
On the last few PRs I have noticed two problems:
1. `ruff format` fails even though it seems OK on our local machines
(sometimes, not always)
2. Nate's and Sam's machines kept flip-flopping a specific piece of
formatting back and forth, indicating a subtle difference of config
hiding somewhere
3. This was reproducible by running `ruff format` in the terminal,
followed by `make check`. The former would edit files, and then `make
check` would edit them back!
This PR addresses both issues, and further standardizes our editor &
linter configs to be super stable.
Specifically:
1. The main fix for the above, the pre-commit hook was pinned to a super
old version of ruff.
This resulted in subtle differences in behavior between our machines,
and on CI.
2. Moved ruff settings from `pyproject.toml` to `.ruff.toml`
pyproject files in subdirectories (e.g. `toolkits/**`) were overriding
the main pyproject file and erasing the custom ruff config we set at the
root. This meant that our ruff config was applied to `arcade` but not to
any of the other packages.
By moving the config to `.ruff.toml` at the root, all projects will
inherit the same ruff linting & formatting config.
4. Un-ignored the `.vscode/` directory so that we can share
vscode/cursor workspace settings.
This is valuable for standardizing settings like the default formatter
(ruff) and default test framework (pytest).
However, it's important that going forward we _only_ commit things here
that should apply across all of our machines.
5. To avoid any conflict between prettier and ruff, prettier now
explicitly ignores *.py files
6. Finally, `ruff format` and `make check` agree. A number of files are
newly auto-formatted.
