Forge

One terminal skill, every harness

The CLI is one lens. Forge is a different form factor.

Forge is a portable, stdlib-only Agent Skill: its repo root is the skill root, and it gives multiple harnesses a shared way to launch, drive, and test terminal applications in persistent Forge PTY sessions — visible in a local dashboard at http://127.0.0.1:3141/ even when the calling harness never exposes Forge as an MCP server.

Next: the proof — one skill, five harnesses, zero pip dependencies.

git@github.com:michaeljabbour/amplifier-skill-forge.git

One shared skill drives five harnesses — zero pip dependencies, ever

Forge gives Claude Code, OpenAI Codex, OpenCode, Gemini, and Microsoft Amplifier a shared way to launch, drive, coordinate, and test terminal apps in persistent PTY sessions.

And tools/forge.py stays python3 stdlib-only — no venv, no pip, executed by arbitrary harnesses. Next: the two files behind it.

Claude Code
OpenAI Codex
OpenCode
Gemini
Microsoft Amplifier

Forge is two files, built in six commits on one day

forge.py is the stdlib JSON-RPC terminal & agent client; relay.py is a resumable multi-agent relay controller. Total tracked source is ~5,166 lines, dominated by references and relay.py.

These are the artifacts the rest of the argument leans on. Next: where it broke.

387 lines
forge.py — 20 terminal + agent-launcher commands
858 lines
relay.py — fail-closed planner→implementer→reviewer→resolver→acceptor, 12 subcommands

The foundation was brittle: every spawn died

After bun install -g updates, node-pty's darwin spawn-helper loses its exec bit — so every PTY spawn fails with posix_spawnp failed. The whole form factor stops working.

A broken foundation threatens everything above it. Next: the discipline that keeps Forge trustworthy under failure.

# after: bun install -g # node-pty spawn-helper loses its exec bit forge new Error: posix_spawnp failed # every terminal create fails

relay.py's gates are fail-closed

A gate advances only when every applicable condition holds. It never treats a timeout or chat response as permission to advance — “a timeout is an observation point, not permission to advance.”

This is how Forge earns trust under failure. Next: how it heals the broken foundation.

The fix lives inside the tool: the skill repairs itself

forge.py doctor detects the posix_spawnp failure, chmods the darwin spawn-helper binaries back to executable (0o755), and restarts the daemon. Repair is codified, not tribal knowledge.

Restoration is now a command, not a memory. Next: the proof that it holds.

  1. 1Detect posix_spawnp in the spawn error
  2. 2chmod 0o755 the darwin spawn-helpers
  3. 3forge stopforge start -d
  4. 4Report: healthy — fixed exec bit, restarted daemon
Restoration proven

The healed form factor goes fully green

After the doctor re-arms the spawn-helper and restarts the daemon, the full suite passes — 29 unit + contract tests across test_forge.py, test_relay.py, and test_skill_contract.py, backed by CI.

Restoration is codified, not manual — the whole suite proves it. Next: what makes that matter.

29
unit + contract tests — “Ran 29 tests … OK”
3.9 & 3.13
Python CI matrix on ubuntu-latest via GitHub Actions

A form factor you can trust heals itself and proves it.

Forge is more than a clever terminal wrapper. It gives five harnesses a shared, persistent terminal; it coordinates them through fail-closed relays; and when its own foundation breaks, forge.py doctor repairs it and 29 tests confirm it. That's the difference between a trick and a tool.

git@github.com:michaeljabbour/amplifier-skill-forge.git

Research Methodology

Primary repo: michaeljabbour/amplifier-skill-forge — a portable Agent Skill & zero-dependency Python toolkit (repo root = skill root).

Feature status: Cross-harness orchestration and doctor-based restoration VERIFIED (29 tests re-run and passing).

Commands run:

  • git remote -v — origin git@github.com:michaeljabbour/amplifier-skill-forge.git
  • git log --format='%H %an <%ae> %ad' --date=iso — 6 commits, Michael J. Jabbour, all 2026-07-16
  • wc -l tools/*.py — forge.py 387, relay.py 858; ~5,166 total tracked lines
  • grep -n 'spawn-helper|posix_spawnp' AGENTS.md references/orchestration-playbook.md — the failure & fix
  • sed -n '175,215p' tools/forge.py — doctor: chmod 0o755 spawn-helpers + forge stop/start -d
  • python3 -m unittest discover -s tests -v — “Ran 29 tests … OK”
  • cat .github/workflows/ci.yml — python 3.9 & 3.13 matrix on ubuntu-latest

Primary contributor: Michael J. Jabbour — sole author of all 6 commits (michael.jabbour@gmail.com).

Gaps & caveats: The “Restoration / Evolution / two-track / PiDrive / Mac mini” framing is editorial and is NOT a literal artifact in the source repos; the only in-repo Mac grounding is the darwin spawn-helpers targeted by doctor. Nothing here is rounded up or inflated.

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