remote-tests

A guide for testing coding-agent features on remote machines instead of only on the local computer. It covers Docker-based Linux executors and Wine-based Windows executors, including how tests opt in and when they may be skipped.

In plain words
What is it for?
Use it when adding or maintaining integration tests for local-versus-remote execution, app servers, execution servers, and platform-specific test skips.
Why use it?
It helps find differences between local execution and the remote environments used by integration tests.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/openai/codex/remote-tests
Any agent
npx skills add openai/codex --skill remote-tests
Clone the repo
git clone --depth 1 https://github.com/openai/codex

Made for: Claude Code, Codex.

Per session 12 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 786 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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.

ModelPer sessionOnce invoked
Fable 5 $0.00012 $0.00786
Opus 5 $0.00006 $0.00393
Sonnet 5 $0.00002 $0.00157
Haiku 4.5 $0.00001 $0.00079

Measured 2d ago against content hash 5029f27ab93f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

remote-tests 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 2d ago.

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.

Origin

Copies of this mod

6 near-identical copies found in the catalogue:

.codex/skills/remote-tests/SKILL.md · 107 lines

How it starts

The opening of the file, as written. The whole thing — 107 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Remote executor tests exercise the app-server/exec-server split to ensure that agent features work in both local and remote execution environments.

Remote executor tests currently require an x86_64 Linux host machine. There are two flavors:

  1. Docker (Linux exec-server)
  2. Wine (Windows exec-server)

Test Fixtures

Individual test cases must opt-in to being run against a remote executor.

codex_core

Use TestCodexBuilder::build_with_auto_env() to opt-in to remote execution in core integration tests unless the test needs more precise control over its executor.

app-server

Start the server with TestAppServer::new_with_auto_env() unless the test defines its own $CODEX_HOME/environments.toml or will define custom environments at runtime.

Start threads with TestAppServer::send_thread_start_request_with_auto_env() if you've created the server with the auto_env approach. Omit ThreadStartParams.environments (leave it as None) when doing so.

Test Skips

If a test doesn't pass in a particular remote executor configuration you can skip it in just that configuration. Include a string reason for future readers when the selected skip macro supports one.

Choose the skip macro by what causes the test to fail:

  • skip_if_target_windows!: Windows target behavior.
  • skip_if_wine_exec!: Wine-exec runner constraints.
  • skip_if_host_windows!: Windows host constraints.
  • skip_if_remote!: Local-only test behavior.
  • skip_if_no_remote_env!: Remote-only test behavior.

Prefer defining tests that run in all host/target configurations by default. See the $path-types skill for the most common changes required to make tests compatible.

Docker

Docker container is built and initialized via ./scripts/test-remote-env.sh. Sourcing this script in bash also provides the codex_remote_env_cleanup function to use after testing.

To run core integration tests against a Docker remote executor:

bash -c '
  set -euo pipefail
  unset CODEX_TEST_REMOTE_EXEC_SERVER_URL
  source scripts/test-remote-env.sh
  trap codex_remote_env_cleanup EXIT

  cd codex-rs
  just test -p codex-core --test all
'

Read the full file on GitHub · 107 lines

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.

  1. 2d ago First seen · 107 lines · 12 tokens per session scan A 5029f27ab93f

Subscribe to this mod's changes

remote-tests is a skill published in the GitHub repository openai/codex (120,598 stars, last pushed today), licensed Apache-2.0. It adds 12 tokens to every session and 786 once invoked, about $0.0001 per session on Opus 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 2026-08-30.

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