Claude-code-skills ln-011-agent-installer

Installs or updates Codex CLI, Gemini CLI, Claude Code, and detects Google Antigravity IDE. Use when CLI agents need installation or update.

install

source · Clone the upstream repo

git clone https://github.com/levnikolaevich/claude-code-skills

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/levnikolaevich/claude-code-skills "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills-catalog/ln-011-agent-installer" ~/.claude/skills/levnikolaevich-claude-code-skills-ln-011-agent-installer && rm -rf "$T"

manifest: skills-catalog/ln-011-agent-installer/SKILL.md

source content

Paths: File paths (
shared/
,
references/
) are relative to skills repo root. Locate this SKILL.md directory and go up one level for repo root.

Agent Installer

Type: L3 Worker Category: 0XX Shared

Installs or updates CLI agents via npm and Claude CLI. Single pass per agent: install then immediately verify.

MANDATORY READ: Load

shared/references/coordinator_summary_contract.md

shared/references/environment_worker_runtime_contract.md

, and

shared/references/worker_runtime_contract.md

Input / Output

Direction Content

Input

OS info,

disabled

flags per agent,

dry_run

flag, optional

runId

, optional

summaryArtifactPath

Output

Structured summary envelope with

payload.status

completed

skipped

error

, plus per-agent install outcomes in

changes

detail

summaryArtifactPath

is provided, write the same summary JSON there. If not provided, return the summary inline and remain fully standalone. If

runId

is not provided, generate a standalone

run_id

before emitting the summary envelope.

Runtime

Runtime family:

environment-worker-runtime

Phase profile:

```
PHASE_0_CONFIG
```
```
PHASE_1_INSTALL_VERIFY
```
```
PHASE_2_POST_GEMINI_CONFIG
```
```
PHASE_3_POST_CODEX_SANITY_CHECK
```
```
PHASE_4_WRITE_SUMMARY
```
```
PHASE_5_SELF_CHECK
```

Runtime rules:

emit
```
summary_kind=env-agent-install
```
standalone runs generate their own
```
run_id
```
and write the default worker-family artifact path
managed runs require both
```
runId
```
and
```
summaryArtifactPath
```
and must write the summary to the exact provided path
always write the validated summary artifact before terminal outcome

Output Contract

Always build a structured

env-agent-install

summary envelope per:

shared/references/coordinator_summary_contract.md

shared/references/environment_worker_runtime_contract.md

Payload fields:

```
targets
```
```
agents_processed
```
```
agents_skipped
```
```
versions
```
```
gemini_settings_updated
```
```
codex_drift_detected
```
```
status
```

Agent Registry

Agent	Install Command	Health Check
Codex	`npm i -g @openai/codex`	`codex --version`
Gemini	`npm i -g @google/gemini-cli`	`gemini --version`
Claude	`claude update`	`claude --version`
Antigravity	manual install via IDE (no CLI)	detect `~/.gemini/antigravity/` directory presence

Workflow

For each agent: Install → Verify → Record

Phase 1: Install & Verify

For each agent in registry, apply first matching rule:

Condition	Action	Report
`disabled: true`	SKIP	"disabled by user"
`dry_run: true`	Show planned command	"dry run"
npm agent	`npm install -g {pkg}` then `{cmd} --version`	version or error
Claude	`claude update` then `claude --version`	version or error

Single pass: install and verify happen atomically per agent. No separate scan phase — the install result IS the state.

Error handling:

Error	Detection	Response
npm not in PATH	`npm --version` fails	FAIL gracefully, report "npm not found in PATH"
Permission denied	stderr contains "EACCES"	FAIL, suggest `npm install -g --prefix ~/.local {pkg}`
Network error	stderr contains "ETIMEDOUT" or "ENETUNREACH"	FAIL, report "network error"
Unknown error	Any other non-zero exit	FAIL, include stderr

Output table:

Agent Installation:
| Agent  | Action    | Version  | Status |
|--------|-----------|----------|--------|
| Codex  | installed | 0.1.2503 | ok     |
| Gemini | skipped   | -        | disabled by user |
| Claude | updated   | 1.0.30   | ok     |

Phase 2: Post-Install Gemini Configuration

After successful Gemini install/update, merge into

~/.gemini/settings.json

Read existing file (or
```
{}
```
if missing)
Deep-merge: set
```
security.enableConseca
```
to
```
false
```
(preserve all other keys — MCP servers, model, trust, etc.)
Write back (2-space indent JSON)
Model — do NOT pass
```
-m
```
flag when invoking Gemini CLI. Auto mode routes to best available model (gemini-3.1-pro / gemini-3-flash).

Phase 2b: Post-Install Codex Mapping Sanity Check

After successful Codex install/update:

Check
```
~/.codex/skills
```
for discovery-visible cache (especially
```
~/.codex/skills/cache/**
```
)

Check

~/.codex/skills/known_marketplaces.json

install locations for foreign paths such as

~/.claude/plugins/...

Check

~/.codex/config.toml

top-level

approval_policy

and

sandbox_mode

If drift is found, report a WARN and defer remediation to
```
ln-013-config-syncer
```

This installer does not relocate Codex cache, rewrite skill mapping, or manage Codex execution defaults. It only reports drift so install success is not mistaken for a healthy Codex environment.

Critical Rules

Never modify
disabled
flags. Respect them, never change them
Fail gracefully. One agent failure does not block others
Global install only. Always
```
npm install -g
```
(CLI tools must be in PATH)
Report all changes. Include config modifications in the final summary table
Idempotent. Safe to run multiple times
Non-destructive config writes. Always read → deep-merge → edit. Never overwrite
```
~/.gemini/settings.json
```
from scratch — it contains MCP servers, hooks, and user preferences managed by other skills.
Codex mapping and execution-default remediation belongs to ln-013. This skill may detect Codex skill-root drift or
```
approval_policy
```
/
```
sandbox_mode
```
drift, but it must not rewrite marketplace/cache layout or Codex top-level permission defaults itself.

Anti-Patterns

DON'T	DO
Separate check/install/verify phases	Single pass: install then verify
Retry failed installs automatically	One attempt, report failure
Use `sudo npm install`	Suggest `--prefix` for permission issues
Install agents marked `disabled`	Skip with clear report
Overwrite entire config file with only known fields	Read existing → deep-merge only owned fields → edit back

Definition of Done

All agents processed in single pass (install + verify)
Disabled agents skipped with report
Version verified immediately after each install
Codex mapping and execution-default sanity checked or explicitly reported for ln-013 follow-up
Status table displayed
Structured summary returned
Summary artifact written to the managed or standalone runtime path

Version: 1.1.0 Last Updated: 2026-03-23