Agentmailbox Claude Code

AgentMailbox — Context Sync for Claude Code

Your context follows you across terminal sessions and tools.

AgentMailbox gives Claude Code persistent memory across sessions. Combined with CLAUDE.md for static project context, AgentMailbox provides dynamic, evolving context that tracks decisions, progress, and open questions across every session and every tool.

Setup

1. Add MCP to Claude Code

Add to your Claude Code MCP settings:

{
  "mcpServers": {
    "agentsmcp": {
      "command": "npx",
      "args": ["-y", "agentsmcp-adapter"],
      "env": {
        "AGENTSMCP_AGENT_ID": "claude-code@local",
        "AGENTSMCP_SERVER": "http://localhost:3000"
      }
    }
  }
}

2. Start the Server

npx agentsmcp-server
# Runs at http://localhost:3000

Or use the demo server:

AGENTSMCP_SERVER=https://hdnxa5c8yr.us-east-1.awsapprunner.com

How It Works with CLAUDE.md

| Layer | Purpose | Persistence | |:------|:--------|:------------| | CLAUDE.md | Static project context (coding standards, architecture, conventions) | File-based, manual | | AgentMailbox | Dynamic session context (decisions, progress, open questions, handoffs) | Server-backed, automatic |

Use both together:

• CLAUDE.md for what the project is
• AgentMailbox for what happened and what's next

Workflows

Session Start

Tool: agentsmcp_receive

Check for context from previous sessions or messages from other agents/tools.

After Terminal Work

Record what you accomplished:

Tool: agentsmcp_send
Arguments:
  to: "claude-code@local"
  body: {
    "session": "Terminal session summary",
    "commands": ["npm test — all passing", "npm run build — clean"],
    "decisions": ["Migrated to ESM modules"],
    "filesChanged": ["package.json", "tsconfig.json", "src/index.ts"],
    "remainingTasks": ["Update CI config for ESM"]
  }

Handoff to GUI Tools

When the user wants to continue in Cursor or Claude Desktop:

Tool: agentsmcp_send
Arguments:
  to: "cursor@local"
  body: {
    "handoff": "ESM migration 80% complete",
    "remainingWork": "Update CI pipeline, fix 2 failing integration tests",
    "context": "See thread for full migration log"
  }

Tool Reference

| Tool | Purpose | |:-----|:--------| | agentsmcp_receive | Get unread messages with full context | | agentsmcp_send | Send a message / record progress | | agentsmcp_sync | Rejoin a thread with full context | | agentsmcp_threads | List all threads | | agentsmcp_mark_read | Mark a thread as read | | agentsmcp_reply_all | Reply to all participants |

Links

• GitHub: https://github.com/RagavRida/agentsmcp
• npm: https://www.npmjs.com/package/agentsmcp

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: RagavRida
• Source: RagavRida/agentsmcp
• License: MIT

Install and usage instructions live in the source repository linked above.