CLI reference - httpmon

Flags

Flag	Type	Default	Description
`--port`	int	`8080`	Proxy listen port
`--data-dir`	string	`~/.httpmon`	Data directory for CA certs and scripts
`--buffer-size`	int	`10000`	Max flows in memory
`--block`	string		Comma-separated host patterns to block
`--allow`	string		Comma-separated host patterns to allow
`--throttle`	string		Throttle preset: `3g`, `4g`, `wifi`
`--latency`	duration	`0`	Added latency per response
`--mcp`	bool	`false`	Start MCP server on `127.0.0.1:9551`
`--mcp-addr`	string		MCP server listen address (implies `--mcp`)
`--mcp-token`	bool	`false`	Print MCP bearer token and exit
`--proto-path`	string		Path to `.proto` file or directory (repeatable)
`--proto-include`	string		Additional import search dir, like protoc `-I` (repeatable)
`--browse`	string		Open URL in default browser with system proxy configured
`--install-ca`	bool	`false`	Install CA cert and exit (needs sudo)
`--version`	bool	`false`	Print version and exit

Usage examples

httpmon                          # Start on default port
httpmon --port 9090              # Custom port
httpmon --block "*.ads.com"      # Block ad hosts
httpmon --allow "api.example.*"  # Only intercept matching
httpmon --throttle 3g            # Simulate 3G
httpmon --throttle wifi --latency 200ms  # WiFi + custom latency
httpmon --mcp                    # Enable MCP server
httpmon --mcp-addr 127.0.0.1:9000  # Custom MCP address
httpmon --mcp-token              # Print MCP bearer token
sudo httpmon --install-ca        # Install CA cert
httpmon --proto-path ./protos           # Decode with field names
httpmon --proto-path a.proto --proto-path b.proto  # Multiple files
httpmon --proto-include ./vendor  # Import search dirs
httpmon --browse https://example.com  # Open browser with proxy configured

The --block and --allow flags accept wildcard patterns with *. You can combine them to control which hosts the proxy intercepts. The --throttle flag applies bandwidth limits and base latency from the selected preset. Use --latency alongside it to override the preset’s latency value. The --proto-path flag enables named Protobuf field decoding. Pass a .proto file or a directory (recursively scans for *.proto). Repeat the flag for multiple paths. Paths are appended to any proto_paths in ~/.httpmon/config.json. The --proto-include flag adds import search directories for proto file resolution, similar to protoc’s -I flag. Repeat for multiple directories. The --browse flag sets the macOS system HTTP/HTTPS proxy to httpmon, opens the given URL in your default browser, and pre-populates the TUI filter with the URL’s hostname. The CA certificate is auto-installed if not already trusted. System proxy settings are restored when httpmon exits.

​Flags

​Usage examples

Flags

Usage examples