hermes - 💡(How to fix) Fix Homebrew bottle 2026.5.16 missing 'mcp' and 'websockets' packages — MCP and browser tools fail at runtime

Summary

The 2026.5.16 (and 2026.5.16_1) Homebrew bottle of hermes-agent installs a Python venv at /opt/homebrew/Cellar/hermes-agent/<version>/libexec/ that does not include the mcp package or the websockets package. As a result, two advertised features fail at runtime:

1. MCP server connections fail for both HTTP/SSE and stdio transports
2. Browser tools fail to import (No module named 'websockets')

Repro

Clean install on macOS arm64 (Apple Silicon):

brew install hermes-agent
hermes mcp add my-server --url https://example.com/mcp --auth header
# → ✗ Failed to connect: MCP server 'my-server' requires HTTP transport but mcp.client.streamable_http is not available. Upgrade the mcp package to get HTTP support.

hermes mcp add my-stdio --command /some/stdio/wrapper.sh
# → ✗ Failed to connect: name 'StdioServerParameters' is not defined

Both transports fail because mcp is absent from the bundled site-packages:

$ find /opt/homebrew/Cellar/hermes-agent/2026.5.16_1 -name "mcp" -type d
(no output)

websockets is also missing, surfaced on hermes startup:

Could not import tool module tools.browser_dialog_tool: No module named 'websockets'

Environment

• macOS 26.4.1 (Darwin 25.4.0), arm64
• Homebrew 5.1.13
• Python 3.14.5 (bundled with bottle)
• hermes-agent 2026.5.16_1

Workaround

Install the missing packages into the brew-managed venv:

/opt/homebrew/Cellar/hermes-agent/<version>/libexec/bin/python -m ensurepip --upgrade
/opt/homebrew/Cellar/hermes-agent/<version>/libexec/bin/python -m pip install --upgrade mcp websockets

After this, hermes mcp add and the browser tools work as documented. The workaround is wiped on every brew upgrade hermes-agent, so users have to re-run it after each version bump.

Suggested fix

Add mcp and websockets to the Homebrew formula's resource block (or whichever PyPI-resource manifest the bottle uses), so the venv ships with them.

Why this matters

These two integrations are prominent on the project's landing page and CLI help text:

• hermes mcp is a top-level command with rich subcommands (add, list, test, serve, configure, etc.)
• Computer-use / browser tools are advertised as a core capability

A clean brew install can use neither without manual venv patching.