Add mcp command for stdio MCP server mode with deploy tool endpoint

[Copilot]

Adds MCP (Model Context Protocol) server support to the deploy4j CLI, enabling AI agent harnesses to invoke deploy4j operations via the standardized MCP stdio transport.

Changes

• New McpCliCommand — picocli subcommand deploy4j mcp that starts an MCP sync server over stdio using io.modelcontextprotocol.sdk:mcp:0.9.0
• deploy MCP tool — exposes the existing deploy logic as an MCP tool endpoint; accepts an optional skipPull boolean parameter, returns success/error text content
• Lifecycle management — wraps System.in in a FilterInputStream that counts down a CountDownLatch on EOF, blocking the main thread until the client closes the connection, then cleanly closes the server
• Dependency — added io.modelcontextprotocol.sdk:mcp:0.9.0 to deploy4j-cli/pom.xml
• Registration — McpCliCommand added to the subcommand list in Deploy4jApplicationCommand

Usage

# Start deploy4j as an MCP server (AI agent connects via stdio)
deploy4j mcp -c config/deploy.yml -d staging

The agent can then call the deploy tool:

{
  "name": "deploy",
  "arguments": { "skipPull": false }
}

This is the first tool endpoint; remaining CLI commands (redeploy, rollback, etc.) can be added as follow-on MCP tools using the same pattern.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• central.sonatype.com
  • Triggering command: /usr/bin/curl curl -s REDACTED (dns block)
• modelcontextprotocol.github.io
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node /home/REDACTED/work/_temp/ghcca-node/node/bin/node --enable-source-maps /home/REDACTED/work/_temp/copilot-developer-action-main/dist/index.js (dns block)
• modelcontextprotocol.io
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node /home/REDACTED/work/_temp/ghcca-node/node/bin/node --enable-source-maps /home/REDACTED/work/_temp/copilot-developer-action-main/dist/index.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

I'd like to add a command called mcp. This will put the tool into mcp server mode, supporting stdio mcp usage.

Use the offficla java mcp sdk https://modelcontextprotocol.io/sdk/java/mcp-server to implement each of the existing cli commands as a mcp tool endpoint.

The tools will be used within an ai agent harness.

We can create a first impl for the deploy command and the rollout the others after.

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💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.