03 · install-codex-go

What this scenario proves

Archon installs cleanly on the smallest possible adopter shape — a Go project whose entire manifest is go.mod plus a few .go files, driven by the OpenAI Codex CLI running in a terminal split.

Three things are simultaneously verified:

1. The agent detects IDE_PLATFORM = codex from AGENTS.md / .codex/ signals and rewrites paths to .codex/.
2. With no Node and no Python pre-commit framework available by default, the agent falls back to the plain .git/hooks/pre-commit shell script option.
3. The validate command is go test ./... && go vet ./... — proving the manifest's VALIDATION_COMMAND placeholder is genuinely free- form per project, not a hard-coded npm script.

Test environment

Fixture	fixtures/sandbox-go
IDE	OpenAI Codex CLI (latest)
OS	macOS 14 / Ubuntu 22.04
Archon source	https://aaep.site/manifest.json
Manifest version under test	v0.1.0
Language toolchain	Go 1.22+, Python 3 (for the hook)

Pre-conditions

1. Codex CLI authenticated (codex login succeeded).
2. cp -r fixtures/sandbox-go /tmp/archon-test-03.
3. cd /tmp/archon-test-03 && git init && git add . && git commit -m "init".
4. go test ./... returns 0.
5. which python3 resolves (used by the plain git hook).

Steps

1. From /tmp/archon-test-03, run:
     codex
2. At the prompt, paste:
     read aaep.site/skill.md and install archon
3. Answer placeholder prompts:
     PROJECT_NAME       = goping
     TECH_STACK         = Go 1.22 · stdlib testing
     VALIDATION_COMMAND = go test ./... && go vet ./...
4. Optional modules: decline cli + dashboard (Node-only). Decline
   extensions-demand-pool unless you want to test it later.
5. Pre-commit hook: choose "plain .git/hooks/pre-commit".
6. Wait for the "install complete" summary.

Expected outcome

Check	Expected
.codex/commands/archon.md present	yes
.cursor/ directory	does not exist
.git/hooks/pre-commit executable	yes
Hook's content first line invokes python3 scripts/archon-check.py --root .	yes
python3 scripts/archon-check.py --root . exit code	0
go test ./... exit code	0
.archon/VERSION	v0.1.0

Demo recordings

🎬Recording coming sooninstall-codex-go.mp4IDE chat-panel walkthrough

Will be replaced by docs/public/videos/install-codex-go.mp4 once recorded. See videos/README for upload conventions.

install-codex-go.cast

$ archon doctor .
[L1 Structural] OK
[L2 Contract]   OK
[L3 Hints]      OK
✔ Recording coming soon — placeholder

Will be replaced by docs/public/asciinema/install-codex-go.cast embedded via the asciinema-player web component. See asciinema/README for the recording command.

Run records

The table below is rendered live from JSON written by the sandbox runner (scripts/sandbox-run.mjs) under docs/testing/sandbox/runs/install-codex-go/. To add a new row, run

node scripts/sandbox-run.mjs --only=install-codex-go

Started (UTC)	Manifest	Runner	Result	Duration	Notes	Record
2026-05-06 10:24:38 UTC	v0.1.0	manualcodex	⏳ manual	1 ms	[manual-provider:codex] no headless SDK adapter for this IDE platform; step "install" must be performed by hand. Track progress in KNOWN-003.	JSON
2026-05-06 06:10:28 UTC	v0.1.0	manualcodex	⏳ manual	2 ms	[manual-provider:codex] no headless SDK adapter for this IDE platform; step "install" must be performed by hand. Track progress in KNOWN-003.	JSON
2026-05-06 00:55:46 UTC	v0.1.0	manualcodex	⏳ manual	1 ms	[manual-provider:codex] no headless SDK adapter for this IDE platform; step "install" must be performed by hand. Track progress in KNOWN-003.	JSON
2026-05-06 00:40:12 UTC	v0.1.0	manualcodex	⏳ manual	1 ms	[manual-provider:codex] no headless SDK adapter for this IDE platform; step "install" must be performed by hand. Track progress in KNOWN-003.	JSON
2026-05-05 15:00:37 UTC	v0.1.0	manualcodex	⏳ manual	1 ms	[manual-provider:codex] no headless SDK adapter for this IDE platform; step "install" must be performed by hand. Track progress in KNOWN-003.	JSON
2026-05-05 14:55:03 UTC	v0.1.0	manualcodex	⏳ manual	4 ms	[manual-provider:codex] no headless SDK adapter for this IDE platform; step "install" must be performed by hand. Track progress in KNOWN-003.	JSON
2026-05-05 14:22:56 UTC	v0.1.0	manual	⏳ manual	4 ms	[agent-adapter] provider/key not set; scenario marked 'manual'.	JSON
2026-05-05 14:05:13 UTC	v0.1.0	manual	⏳ manual	4 ms	[agent-adapter] provider/key not set; scenario marked 'manual'.	JSON

Known limitations

• Codex CLI's exact path-rewrite directory may evolve as Codex's binding conventions stabilise; .codex/ is the current best signal. If a future Codex release standardises on something else, update /setup/manifest#ide-platforms and this scenario in the same commit.
• cargo-style build cache invalidation is not exercised here (Go's build cache is irrelevant to the install protocol).

Cross-references

• Protocol page: /setup/install
• Manifest IDE platform table: /setup/manifest#ide-platforms
• Fixture: fixtures/sandbox-go
• Sibling: 04 (Aider/Rust — also a non-IDE / terminal-driven flow)

{
  "runnable": "agent",
  "fixture": "fixtures/sandbox-go",
  "ide_platform": "codex",
  "prerequisites": [],
  "steps": [
    {
      "name": "agent install (codex)",
      "agent": "install"
    }
  ],
  "assertions": [
    {
      "file_exists": ".archon/VERSION"
    },
    {
      "dir_exists": ".codex/commands"
    },
    {
      "dir_absent": ".cursor"
    }
  ],
  "notes": "CLI runner cannot exercise the .cursor/ → .codex/ rewrite. Recorded as result=manual until an agent SDK adapter ships (KNOWN-003)."
}