MCP Client

MCP Client Skill

Universal MCP client for connecting to any MCP server directly from a skill. This replaces the old multi-agent pattern where the parent agent held all MCP tools — instead, each skill spawns its own MCP connection with only the tools it needs.

Usage

The mcp_client.py script is a robust, universal client. It separates informative logs (stderr) from machine-readable results (stdout), making it ideal for agent consumption.

General Options

List Available Tools

# From a local MCP server (stdio)
python -m universal_skills.skills.mcp-client.scripts.mcp_client \
    --command servicenow-mcp \
    --args "--transport stdio" \
    --env INCIDENTSTOOL=True \
    --env CMDBTOOL=False \
    --action list-mcp-tools

# From a remote MCP server (HTTP)
python -m universal_skills.skills.mcp-client.scripts.mcp_client \
    --url http://github-mcp:8787/mcp \
    --action list-mcp-tools

# From an mcp_config.json
python -m universal_skills.skills.mcp-client.scripts.mcp_client \
    --config mcp_config.json \
    --server my-server \
    --action list-mcp-tools

Call a Specific Tool

You can pass arguments as a JSON string or as a path to a JSON file.

Option A: JSON String

python -m universal_skills.skills.mcp-client.scripts.mcp_client \
    --command servicenow-mcp \
    --args "--transport stdio" \
    --env INCIDENTSTOOL=True \
    --dotenv .env \
    --action call-mcp-tool \
    --tool-name get_incidents \
    --tool-args '{"sysparm_limit": "5"}'

Option B: JSON File

# Create an arguments file
echo '{"sysparm_limit": "10", "sysparm_query": "active=true"}' > args.json

# Call the tool using the file
python -m universal_skills.skills.mcp-client.scripts.mcp_client \
    --command servicenow-mcp \
    --args "--transport stdio" \
    --dotenv .env \
    --action call-mcp-tool \
    --tool-name get_incidents \
    --tool-args args.json

Advanced: ServiceNow Flow to Mermaid

Generate full relationship diagrams for ServiceNow Flow Designer flows:

# 1. Prepare your .env with ServiceNow credentials
# 2. Call the workflow_to_mermaid tool
python -m universal_skills.skills.mcp-client.scripts.mcp_client \
    --command servicenow-mcp \
    --dotenv .env \
    --action call-mcp-tool \
    --tool-name workflow_to_mermaid \
    --tool-args '{"flow_identifiers": ["sys_id_1", "sys_id_2"], "save_to_file": true, "output_dir": "."}'

The tool will generate a Markdown file containing the Mermaid diagrams, which you can then view in any Mermaid-compatible viewer.

Generate an mcp_config.json

Generate a config that enables only one tool tag and disables all others:

python -m universal_skills.skills.mcp-client.scripts.mcp_client \
    --action generate-mcp-config \
    --mcp-command servicenow-mcp \
    --enable-tag INCIDENTSTOOL \
    --all-tags "MISCTOOL,FLOWSTOOL,APPLICATIONTOOL,CMDBTOOL,CICDTOOL,PLUGINSTOOL,INCIDENTSTOOL,TABLE_APITOOL" \
    -o mcp_config.json

List Resources and Prompts

python -m universal_skills.skills.mcp-client.scripts.mcp_client --config mcp_config.json --action list-mcp-resources
python -m universal_skills.skills.mcp-client.scripts.mcp_client --config mcp_config.json --action list-mcp-prompts

Programmatic Usage

The script exposes two key functions for import:

from universal_skills.skills.mcp_client.scripts.mcp_client import (
    create_mcp_client,
    generate_mcp_config,
)

# Generate a focused config
config = generate_mcp_config(
    mcp_command="servicenow-mcp",
    enable_tag="INCIDENTSTOOL",
    all_tags=["MISCTOOL", "INCIDENTSTOOL", "CMDBTOOL"],
)

# Create and use the client
import asyncio, json, tempfile
from pathlib import Path

async def main():
    cfg_path = Path(tempfile.mktemp(suffix=".json"))
    cfg_path.write_text(json.dumps(config))
    client = await create_mcp_client(cfg_path)
    async with client:
        tools = await client.list_tools()
        result = await client.call_tool("get_incidents", {"sysparm_limit": "5"})
        print(result)

asyncio.run(main())

Arguments Reference

Troubleshooting

• Timeout Errors: If you see "Operation timed out", increase the --timeout value (e.g., --timeout 120).
• Connection Refused: Ensure the MCP server is running and the --url or --command is correct.
• Dependency Issues: Run with --debug to see detailed import or protocol errors.
• No Result on stdout: Check stderr for errors. If using call-tool, the script should always output a JSON response even on failure.

References

The references/ directory contains ready-to-use documentation and mcp_config.json files for each MCP server. Each .md has stdio (default) + HTTP connection examples, available tool tags, and single-tag config examples.

Dependencies

• fastmcp (required)