mcpc CLAUDE.md

Project guidance for mcpc, a command-line client that connects AI agents and scripts to MCP servers. MCP servers provide tools, data, and prompts over connections such as HTTP or standard input and output.

In plain words
What is it for?
Use it to develop, build, test, or operate mcpc, or to manually test MCP servers and connect coding agents to them.
Why use it?
It explains how to connect to servers, manage login credentials and long-running sessions, and test or script MCP features from a terminal.

Instructions file

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/apify/mcpc/claude-md
Clone the repo
git clone --depth 1 https://github.com/apify/mcpc
Per session 12,611 This file is loaded in full into every session.
When invoked 12,611 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.12611 $0.12611
Opus 5 $0.06305 $0.06305
Sonnet 5 $0.02522 $0.02522
Haiku 4.5 $0.01261 $0.01261

Measured 2d ago against content hash 019dd8f08dbb, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

mcpc CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

CLAUDE.md · 853 lines

How it starts

The opening of the file, as written. The whole thing — 853 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

mcpc is a universal command-line client for the Model Context Protocol (MCP), which maps MCP to intuitive CLI commands for shell access, scripts, and AI coding agents.

mcpc can connect to any MCP server over Streamable HTTP or stdio transports, securely login via OAuth credentials and store credentials, and keep long-term sessions to multiple servers in parallel. It supports all major MCP features, including tools, resources, prompts, asynchronous tasks, and notifications.

mcpc is handy for manual testing of MCP servers, scripting, and AI coding agents to use MCP in "code mode", for better accuracy and lower tokens compared to traditional tool function calling. After all, UNIX-compatible shell script is THE most universal coding language, for both people and LLMs.

Key capabilities:

  • Universal MCP client - Works with any MCP server over Streamable HTTP or stdio
  • Persistent sessions - Keep multiple server connections alive simultaneously
  • Zero setup - Connect to remote servers instantly with just a URL
  • Full protocol support - Tools, resources, prompts, dynamic discovery, and async notifications
  • --json output - Easy integration with jq, scripts, and other CLI tools
  • AI-friendly - Designed for code generation and automated workflows
  • Secure - OS keychain integration for credentials, encrypted auth storage

Build and Development Commands

# Install dependencies
pnpm install

# Build the project
pnpm run build

# Run tests
pnpm test

# Test locally after building
pnpm link --global
mcpc --help

# Run linter/formatter (if configured)
pnpm run lint
pnpm run format

Quick Start Examples

# List all active sessions and saved authentication profiles
mcpc

# Login to OAuth-enabled MCP server and save authentication for future use
mcpc login mcp.apify.com

# Create a persistent session
mcpc connect mcp.apify.com @test
mcpc @test                               # show session info
mcpc @test tools-list                    # list available tools
mcpc @test tools-call search-actors query:="web crawler"

# Use JSON mode for scripting
mcpc --json @test tools-list

# Use a local server package referenced by MCP config file
mcpc connect ~/.vscode/mcp.json:filesystem @fs
mcpc @fs tools-list

Read the full file on GitHub · 853 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 853 lines · 12,611 tokens per session scan A 019dd8f08dbb

Subscribe to this mod's changes

mcpc CLAUDE.md is an instructions file published in the GitHub repository apify/mcpc (761 stars, last pushed yesterday), licensed Apache-2.0. It adds 12,611 tokens to every session, about $0.0631 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.