Model Sherpa

What Model Sherpa does

Model Sherpa is a Hermes Agent plugin that sits between the model and the Hermes tool registry as middleware. Its Arg Guard validates tool calls against their JSON schema, repairs curly quotes, maps wrong key names such as file_path to path, and has dedicated repair logic for the patch tool. Sequence Loop Detection spots simple repeats, ping-pong loops and longer cycles, then injects a nudge so the model changes approach.

A range-aware Read Damper lets the model page through a file but blocks a read already contained in an earlier range in the same turn. Logs mask any key containing api_key, token, password or secret, and non-UTF8 tool results become a compact placeholder. It is zero-config, with guide-rails switched using commands such as /sherpa doctor and /sherpa feature read_damper off. CI runs a 194-test suite on Ubuntu and Windows across Python 3.9 to 3.13. It hooks the Hermes tool registry and is not framework-agnostic today.

Key features

• Schema validation, smart-quote repair and fuzzy key normalization for tool arguments
• Sequence Loop Detection for repeats, ping-pong loops and longer cycles
• Range-aware Read Damper that allows paging but blocks contained re-reads
• Substring redaction of api_key, token, password and secret values in logs
• /sherpa doctor diagnostic and per-feature toggles
• Linux, macOS and Windows support

When to use it

• Stop a model from burning tokens by repeating the same failing tool call
• Fix curly-quoted or misnamed tool arguments without a failed run
• Keep API keys out of session logs

Who it is for: Hermes Agent users who see hallucinated tool parameters, looping behavior or secrets in their logs.

How it fits with Hermes Agent

It is built as a Hermes Agent plugin that hooks the Hermes tool registry. The README says it is not framework-agnostic today, and an MCP server port is only on the roadmap.

How to install Model Sherpa

These commands are copied from the project's README. Check the repository for the latest steps before you run them.

hermes plugins install nordicnode/model-sherpa

Requirements: Hermes Agent; CI covers Python 3.9 to 3.13 on Ubuntu and Windows

Note: It hooks the Hermes tool registry and is not framework-agnostic; an MCP server port is only on the roadmap.

FAQ