MCP-CLI

Access MCP servers through the command line. MCP enables interaction with external systems like GitHub, filesystems, databases, and APIs.

Commands

Command	Output
mcp-cli	List all servers and tools
mcp-cli info <server>	Show server tools and parameters
mcp-cli info <server> <tool>	Get tool JSON schema
mcp-cli grep "<pattern>"	Search tools by name
mcp-cli call <server> <tool>	Call tool (reads JSON from stdin if no args)
mcp-cli call <server> <tool> '<json>'	Call tool with arguments

Both formats work: <server> <tool> or <server>/<tool>

Workflow

1. Discover: mcp-cli → see available servers
2. Explore: mcp-cli info <server> → see tools with parameters
3. Inspect: mcp-cli info <server> <tool> → get full JSON schema
4. Execute: mcp-cli call <server> <tool> '<json>' → run with arguments

Examples

# List all servers
mcp-cli

# With descriptions
mcp-cli -d

# See server tools
mcp-cli info filesystem

# Get tool schema (both formats work)
mcp-cli info filesystem read_file
mcp-cli info filesystem/read_file

# Call tool
mcp-cli call filesystem read_file '{"path": "./README.md"}'

# Pipe from stdin (no '-' needed!)
cat args.json | mcp-cli call filesystem read_file

# Search for tools
mcp-cli grep "*file*"

# Extract text from result
mcp-cli call filesystem read_file '{"path": "./file"}' | jq -r '.content[0].text'

Advanced Chaining

# Chain: search files → read first match
mcp-cli call filesystem search_files '{"path": ".", "pattern": "*.md"}' \
  | jq -r '.content[0].text | split("\n")[0]' \
  | xargs -I {} mcp-cli call filesystem read_file '{"path": "{}"}'

# Loop: process multiple files
mcp-cli call filesystem list_directory '{"path": "./src"}' \
  | jq -r '.content[0].text | split("\n")[]' \
  | while read f; do mcp-cli call filesystem read_file "{\"path\": \"$f\"}"; done

# Conditional: check before reading
mcp-cli call filesystem list_directory '{"path": "."}' \
  | jq -e '.content[0].text | contains("README")' \
  && mcp-cli call filesystem read_file '{"path": "./README.md"}'

# Multi-server aggregation
{
  mcp-cli call github search_repositories '{"query": "mcp", "per_page": 3}'
  mcp-cli call filesystem list_directory '{"path": "."}'
} | jq -s '.'

# Save to file
mcp-cli call github get_file_contents '{"owner": "x", "repo": "y", "path": "z"}' \
  | jq -r '.content[0].text' > output.txt

jq tips: -r raw output, -e exit 1 if false, -s slurp multiple inputs

Options

Flag	Purpose
-d	Include descriptions
-c <path>	Specify config file

Common Errors

Wrong Command	Error	Fix
mcp-cli server tool	AMBIGUOUS_COMMAND	Use call server tool or info server tool
mcp-cli run server tool	UNKNOWN_SUBCOMMAND	Use call instead of run
mcp-cli list	UNKNOWN_SUBCOMMAND	Use info instead of list
mcp-cli call server	MISSING_ARGUMENT	Add tool name
mcp-cli call server tool {bad}	INVALID_JSON	Use valid JSON with quotes

Exit Codes

• 0: Success
• 1: Client error (bad args, missing config)
• 2: Server error (tool failed)
• 3: Network error