cross-harness-sub-agent SKILL.md skillA
cross-harness-sub-agent from nicholas-greenwood/agentic-engineering-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add nicholas-greenwood/agentic-engineering-skills/cross-harness-sub-agent@git:20261020.a5a8115Pins git:20261020.a5a8115 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- nicholas-greenwood/agentic-engineering-skills
- Path
cross-harness-sub-agent/SKILL.md- Versions recorded
- 1
- Latest version
- git:20261020.a5a8115, committed Oct 20, 2026
- Size
- 2,108 bytes
- Repository stars
- 3
- License
- MIT
spawn a cross harness sub-agent.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
## route - from codex, follow [claude-subagent.md](claude-subagent.md) - from claude code, follow [codex-subagent.md](codex-subagent.md) - from another harness, try claude code first, fallback to codex if it failed - the calling agent invokes the selected route directly - an explicit user target, model or effort wins - never use this for same harness sub-agents ## checkout `<checkout>` is an absolute path you reuse literally in every later command: - current checkout: the output of `git rev-parse --show-toplevel` - separate worktree: the last output line of `bin/wt-run HEAD -- pwd` max 1 writer per checkout ## task give the sub-agent a self-contained prompt with the objective, scope, completion condition, edit permission and any context it can't discover require the sub-agent to read `~/.agents/AGENTS.md` when present and applicable repository/project `AGENTS.md` before starting unless the user gives another review scope, compare the current branch with `origin/develop` and include committed branch changes plus staged, unstaged and untracked changes …
Read the whole file at its exact version.
How to install
mdr add nicholas-greenwood/agentic-engineering-skills/cross-harness-sub-agent@sha256:359881dffd5098e8The line at the top of this page pins the label git:20261020.a5a8115, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_ssfc5irxqdo2ypez)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Oct 20, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (2108 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
nicholas-greenwood/agentic-engineering-skills · 3 stars · license MIT · pushed 2026-11-07 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_ssfc5irxqdo2ypez GET https://markdownregistry.com/api/v1/resolve?ref=nicholas-greenwood/agentic-engineering-skills/cross-harness-sub-agent GET https://markdownregistry.com/api/v1/blob/359881dffd5098e8f85d73cf669122a1692fa2661a05ea8c8fb3f0ea83053339
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.