What is multi-harness?

A coordinator for sending limited coding tasks to other local coding-agent programs, called harnesses, such as Pi, OpenCode, Codex CLI, Claude Code CLI, and DHS.

Delegating explicitly requested work to another coding-agent program, comparing models or harnesses, and handling requests that require an external runtime.

It helps when a requested model or runtime is available only through another command-line tool, while keeping the task boundaries and results under review.

multi-harness — Skill for Codex by LFTPadilla/agent-dev-kit

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.

Any agent

npx skills add LFTPadilla/agent-dev-kit --skill multi-harness

Clone the repo

git clone --depth 1 https://github.com/LFTPadilla/agent-dev-kit

Made for: Codex.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/lftpadilla/agent-dev-kit/multi-harness/github.svg)](https://agentmods.dev/skills/lftpadilla/agent-dev-kit/multi-harness)

Your own site

<a href="https://agentmods.dev/skills/lftpadilla/agent-dev-kit/multi-harness"><img src="https://agentmods.dev/badge/skills/lftpadilla/agent-dev-kit/multi-harness/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/lftpadilla/agent-dev-kit/multi-harness"><img src="https://agentmods.dev/badge/skills/lftpadilla/agent-dev-kit/multi-harness.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 75 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,900 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00075	$0.01900
Opus 5.5	$0.00030	$0.00760
Sonnet 5.5	$0.00015	$0.00380
Haiku 4.5	$0.00007	$0.00190

Measured 2mo ago against content hash 3e2666c8448e, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

multi-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 2mo ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/delegate.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

overnight-task-kit/skills/multi-harness/SKILL.md · 140 lines

How it starts

The opening of the file, as written. The whole thing — 140 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Multi Harness (Universal Harness Adapter)

Coordinate local agent harnesses without losing control of scope, safety, or verification.

Use this skill as the primary agent. You remain the orchestrator: decide what to delegate, run the external harness, inspect its output and any file changes, then synthesize the result for the user.

Routing Gate

Apply this gate before diagnostics, profile selection, or running delegate.py:

Default to the current harness's native subagents when they expose the requested model. Requests for generic subagents, workers, parallelism, or orchestration are not external-harness requests.
Use this skill only with an explicit external signal: Pi, OpenCode, Codex CLI, Claude Code CLI, DHS, another/external/cross harness, multiple distinct harnesses, harness comparison, or an external-only runtime the user has asked to use.
When the user explicitly requests an external runtime or specific CLI model, use the Universal Harness Adapter (delegate.py).
If this skill was auto-triggered without an explicit external signal, do not run diagnostics or delegation scripts. Continue using the current harness's native subagent tools.
If the requested harness or model is not available locally, report the limitation and ask for confirmation before switching to an alternative model, harness, or native subagents. Never silently substitute.

Examples:

"Spawn three Codex subagents" -> use native Codex subagents when exposed; if unavailable, report the limitation and confirm before using the Codex CLI profile.
"Parallelize the review with subagents" -> native subagents; do not use multi-harness.
"Delegate this review to Pi with GLM or DeepSeek" -> use multi-harness.
"Run this implementation via DeepSeek Harness (DHS/DSH) or OpenCode" -> use multi-harness.

Universal CLI Harness Execution

The adapter supports running bounded tasks across:

Codex CLI: codex exec --ephemeral [-m <model>] [-C <dir>] [--yolo]
Claude Code CLI: claude -p "<prompt>" [--dangerously-skip-permissions]
DeepSeek Harness (DHS / DSH): dsh exec --dir <dir> [--model <model>] [--yolo] (Headless execution engine; no terminal TUI)
Pi: pi --print --mode text [--model <model>] --tools <tools>
OpenCode: opencode run --dir <dir> [--model <model>] [--auto]

Read the full file on GitHub · 140 lines

Files

What ships with it

5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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.

2mo ago First seen · 140 lines · 75 tokens per session scan A 3e2666c8448e

Subscribe to this mod's changes

multi-harness is a skill published in the GitHub repository LFTPadilla/agent-dev-kit (2 stars, last pushed today), licensed MIT. It adds 75 tokens to every session and 1,900 once invoked, about $0.0003 per session on Opus 5.5. 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.

Building agents Claude Code Code review LLM agent-skills ai-agents developer-tools

multi-harness next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
multi-harnessLFTPadilla/agent-dev-kit	Skill	2	today	MIT	A	75	Codex
requesting-code-reviewNousResearch/hermes-agent	Skill	261k	today	MIT	A	20	Claude Code, Codex
otto-pr-review-loopomnigent-ai/omnigent	Skill	11k	today	Apache-2.0	A	17	Claude Code, Codex
meta-codereview-current-diffopensquilla/opensquilla	Skill	7.1k	6d ago	Apache-2.0	A	73	Claude Code, Codex
prs-awaiting-maintainerdyoshikawa/rulesync	Skill	1.6k	today	MIT	A	56	Claude Code, Codex
review-exportSnowflake-Labs/cocoplus	Skill	727	2d ago	MIT	A	0	Claude Code
review-prdyoshikawa/rulesync	Skill	1.6k	today	MIT	A	61	Claude Code, Codex