RTK Plugin for Hermes

Rewrites Hermes terminal tool commands to RTK equivalents before execution, so Hermes receives compact command output without changing your workflow.

Installation

rtk init --agent hermes

The installer writes the plugin to ~/.hermes/plugins/rtk-rewrite/ and enables it through plugins.enabled in the Hermes config. The repository copy lives in hooks/hermes/; don't use that repo path as the runtime install path.

Development

Run the Hermes plugin tests from the repository root:

python3 -m unittest discover -s hooks/hermes

How it works

Hermes loads plugins from Python, so the plugin entrypoint is Python. The Python code is only a thin Hermes adapter. It reads the Hermes terminal tool payload, calls rtk rewrite for the actual command decision, then mutates the terminal tool command before Hermes executes it.

All rewrite rules stay in Rust inside rtk rewrite. When RTK adds or changes command rewrite behavior, the Hermes plugin picks up that behavior by delegating to the RTK binary.

Fail-open behavior

The plugin does not block command execution. If anything goes wrong, Hermes runs the original command unchanged.

If rtk is not available in PATH when Hermes loads the plugin, the plugin prints a warning and skips hook registration.

• rtk is missing from PATH
• rtk rewrite exits with an error
• Hermes sends a non-terminal tool call
• The tool payload has no string command
• The plugin raises an unexpected exception

Limitations

• Only Hermes terminal tool calls are rewritten.
• Commands skipped by rtk rewrite stay unchanged, including commands already prefixed with rtk, compound shell commands, heredocs, and commands without an RTK filter.
• Shell hooks are not used for Hermes command rewriting. The integration depends on Hermes loading Python plugins and passing a mutable terminal tool payload.