hermes-harness

hermes-harness is a cursor rule for Cursor from Cosmic-Construct/hermes-cursor-harness. It costs 12 tokens per session (198 once invoked), scanned A, original, MIT.

Instructions for coordinating coding work between Hermes and Cursor. Hermes is the outer system that keeps the session and user intent, while Cursor performs project work such as editing files and running commands.

In plain words
What is it for?
Checking harness status, preserving the assigned permission mode, making focused repository changes, and reporting which files were edited.
Why use it?
It prevents session context and permission settings from being lost when work moves between the two tools.

Cursor rule for Cursor

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/cosmic-construct/hermes-cursor-harness/hermes-harness
Clone the repo
git clone --depth 1 https://github.com/Cosmic-Construct/hermes-cursor-harness

Made for: Cursor.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for hermes-harness

README.md
[![agentmods](https://agentmods.dev/badge/rules/cosmic-construct/hermes-cursor-harness/hermes-harness.svg)](https://agentmods.dev/rules/cosmic-construct/hermes-cursor-harness/hermes-harness)
Your own site
<a href="https://agentmods.dev/rules/cosmic-construct/hermes-cursor-harness/hermes-harness"><img src="https://agentmods.dev/badge/rules/cosmic-construct/hermes-cursor-harness/hermes-harness.svg" alt="Measured on agentmods" height="20"></a>
Per session 12 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 198 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00012 $0.00198
Opus 5 $0.00006 $0.00099
Sonnet 5 $0.00002 $0.00040
Haiku 4.5 $0.00001 $0.00020

Measured 4d ago against content hash b2cce277130a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

hermes-harness scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.cursor/plugins/hermes-harness/rules/hermes-harness.mdc · 22 lines

What it actually says

When a task is being driven by Hermes, preserve Hermes as the outer runtime: session state, approval policy, high-level intent, memory context, and final transcript belong to Hermes. Use Cursor for repo-local coding work, tool calls, analysis, edits, and shell execution.

If the Hermes Cursor Harness MCP server is available, use its read-only tools to inspect Hermes session status, project context, and recent harness events before making broad repo changes. These tools are context lookups, not approval to edit files.

If hermes_cursor_sdk_status is available, it can confirm whether Hermes is driving you through the official Cursor SDK bridge.

When Hermes supplied a permission mode, keep your work inside that mode. In plan or ask mode, do not edit files. In edit mode, make focused repo changes and report the exact files touched.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 4d ago First seen · 22 lines · 12 tokens per session scan A b2cce277130a

Subscribe to this mod's changes

hermes-harness is a cursor rule published in the GitHub repository Cosmic-Construct/hermes-cursor-harness (5 stars, last pushed 4mo ago), licensed MIT. It adds 12 tokens to every session and 198 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.