Integrate Serena MCP server for C++ semantic analysis in SpecBot

[Copilot]

The SpecBot workflow performs LLM-based specification mining but lacked semantic code understanding capabilities for C++ analysis.

Changes

• Added Serena MCP server to .github/workflows/specbot.md under mcp-servers: section
• Uses ghcr.io/githubnext/serena-mcp-server:latest container image
• Auto-detects C++ via file extensions (clangd LSP backend)

Configuration

mcp-servers:
  serena:
    container: "ghcr.io/githubnext/serena-mcp-server"
    version: "latest"

Note: C++ is not available in the simple serena: ["cpp"] tool format (only go, typescript, python, java, rust, csharp). The MCP server approach provides full language server support with workspace mounting and semantic analysis capabilities.

Impact

Enables the SpecBot agent to:

• Query type information and call graphs
• Navigate symbol definitions and references
• Understand C++ semantics for more accurate invariant synthesis
• Leverage LSP-based code comprehension alongside LLM reasoning

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:

• githubnext.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)

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

Update the SpecBot workflow to integrate Serena, described here: https://githubnext.github.io/gh-aw/guides/serena/

Custom agent used: agentic-workflows
GitHub Agentic Workflows (gh-aw) - Create, debug, and upgrade AI-powered workflows with intelligent prompt routing

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