-
securityA
license-
qualityAn MCP server that exposes HTTP methods defined in an OpenAPI specification as tools, enabling interaction with APIs via the Model Context Protocol.
Last updated -
8
MIT License
Provides secure authentication for APIs through 1Password secret references, allowing the retrieval of credentials stored in 1Password vaults.
emcee
emcee is a tool that provides a server for any web application with an specification. You can use emcee to connect and to external tools and data services, similar to .
Quickstart
If you're on macOS and have installed, you can get up-and-running quickly.
# Install emcee
brew install loopwork-ai/tap/emcee
Make sure you have Claude Desktop installed.
To configure Claude Desktop for use with emcee:
Open Claude Desktop Settings (⌘,)
Select the "Developer" section in the sidebar
Click "Edit Config" to open the configuration file
The configuration file should be located in the Application Support directory. You can also open it directly in VSCode using:
code ~/Library/Application\ Support/Claude/claude_desktop_config.json
Add the following configuration to add the weather.gov MCP server:
{
"mcpServers": {
"weather": {
"command": "emcee",
"args": [
"https://api.weather.gov/openapi.json"
]
}
}
}
After saving the file, quit and re-open Claude. You should now see 🔨57 in the bottom right corner of your chat box. Click on that to see a list of all the tools made available to Claude through MCP.
Start a new chat and ask it about the weather where you are.
What's the weather in Portland, OR?
Claude will consult the tools made available to it through MCP and request to use one if deemed to be suitable for answering your question. You can review this request and either approve or deny it.
If you allow, Claude will communicate with the MCP and use the result to inform its response.
TIP
Building agents? Want to deploy remote MCP servers? Reach out to us atemcee@loopwork.com
Why use emcee?
MCP provides a standardized way to connect AI models to tools and data sources. It's still early days, but there are already a variety of for connecting to browsers, developer tools, and other systems.
We think emcee is a convenient way to connect to services that don't have an existing MCP server implementation — especially for services you're building yourself. Got a web app with an OpenAPI spec? You might be surprised how far you can get without a dashboard or client library.
Installation
Installer Script
Use the to download and install a of emcee for your platform (Linux x86-64/i386/arm64 and macOS Intel/Apple Silicon).
# fish
sh (curl -fsSL https://get.emcee.sh | psub)
# bash, zsh
sh <(curl -fsSL https://get.emcee.sh)
Homebrew
Install emcee using from .
brew install loopwork-ai/tap/emcee
Docker
Prebuilt with emcee are available.
docker run -it ghcr.io/loopwork-ai/emcee
Build From Source
Requires or later.
git clone https://github.com/loopwork-ai/emcee.git
cd emcee
go build -o emcee cmd/emcee/main.go
Once built, you can run in place (./emcee)
or move it somewhere in your PATH, like /usr/local/bin.
Usage
Usage:
emcee [spec-path-or-url] [flags]
Flags:
--basic-auth string Basic auth value (either user:pass or base64 encoded, will be prefixed with 'Basic ')
--bearer-auth string Bearer token value (will be prefixed with 'Bearer ')
-h, --help help for emcee
--raw-auth string Raw value for Authorization header
--retries int Maximum number of retries for failed requests (default 3)
-r, --rps int Maximum requests per second (0 for no limit)
-s, --silent Disable all logging
--timeout duration HTTP request timeout (default 1m0s)
-v, --verbose Enable debug level logging to stderr
--version version for emcee
emcee implements Standard Input/Output (stdio) transport for MCP, which uses JSON-RPC 2.0 as its wire format.
When you run emcee from the command-line, it starts a program that listens on stdin, outputs to stdout, and logs to stderr.
Authentication
For APIs that require authentication, emcee supports several authentication methods:
Authentication Type | Example Usage | Resulting Header |
Bearer Token |
|
|
Basic Auth |
|
|
Raw Value |
|
|
These authentication values can be provided directly or as .
When using 1Password references:
Use the format
op://vault/item/field(e.g.--bearer-auth="op://Shared/X/credential")Ensure the 1Password CLI () is installed and available in your
PATHSign in to 1Password before running emcee or launching Claude Desktop
# Install op
brew install 1password-cli
# Sign in 1Password CLI
op signin
{
"mcpServers": {
"twitter": {
"command": "emcee",
"args": [
"--bearer-auth=op://shared/x/credential",
"https://api.twitter.com/2/openapi.json"
]
}
}
}
IMPORTANT
emcee doesn't use auth credentials when downloading
OpenAPI specifications from URLs provided as command arguments.
If your OpenAPI specification requires authentication to access,
first download it to a local file using your preferred HTTP client,
then provide the local file path to emcee.
Transforming OpenAPI Specifications
You can transform OpenAPI specifications before passing them to emcee using standard Unix utilities. This is useful for:
Selecting specific endpoints to expose as tools with or
Modifying descriptions or parameters with
Combining multiple specifications with
For example,
you can use jq to include only the point tool from weather.gov.
cat path/to/openapi.json | \
jq 'if .paths then .paths |= with_entries(select(.key == "/points/{point}")) else . end' | \
emcee
JSON-RPC
You can interact directly with the provided MCP server by sending JSON-RPC requests.
NOTE
emcee provides only MCP tool capabilities. Other features like resources, prompts, and sampling aren't yet supported.
List Tools
{"jsonrpc": "2.0", "method": "tools/list", "params": {}, "id": 1}
{
"jsonrpc":"2.0",
"result": {
"tools": [
// ...
{
"name": "tafs",
"description": "Returns Terminal Aerodrome Forecasts for the specified airport station.",
"inputSchema": {
"type": "object",
"properties": {
"stationId": {
"description": "Observation station ID",
"type": "string"
}
},
"required": ["stationId"]
}
},
// ...
]
},
"id": 1
}
Call Tool
{"jsonrpc": "2.0", "method": "tools/call", "params": { "name": "taf", "arguments": { "stationId": "KPDX" }}, "id": 1}
{
"jsonrpc":"2.0",
"content": [
{
"type": "text",
"text": /* Weather forecast in GeoJSON format */,
"annotations": {
"audience": ["assistant"]
}
}
]
"id": 1
}
Debugging
The is a tool for testing and debugging MCP servers. If Claude and/or emcee aren't working as expected, the inspector can help you understand what's happening.
npx @modelcontextprotocol/inspector emcee https://api.weather.gov/openapi.json
# 🔍 MCP Inspector is up and running at http://localhost:5173 🚀
open http://localhost:5173
License
emcee is licensed under the Apache License, Version 2.0.
This server cannot be installed
hybrid server
The server is able to function both locally and remotely, depending on the configuration or use case.
Generate an MCP server for any OpenAPI documented endpoint.
Related MCP Servers
- AsecurityAlicenseAqualityA TypeScript-based MCP server that generates API clients from OpenAPI specifications, allowing automated code generation through natural language.Last updated -11381MIT License
- -securityAlicense-qualityA framework to use with AI to easily create a server for any service. Just drop the API Documentation in it and ask to create the MCP.Last updated -5MIT License
- -securityFlicense-qualityAn auto-generated MCP server that enables interaction with the OpenAI API, allowing users to access OpenAI's models and capabilities through the Multi-Agent Conversation Protocol.Last updated -