What is opencode-sync-sandbox?

A sandbox-first workflow for changing and validating an OpenCode-synced plugin. It requires a plan, tests, local checks, and an isolated end-to-end run before the work is considered complete.

Use it when modifying sync behavior, configuration handling, command execution, repository operations, or related paths, then review the test and end-to-end results.

It reduces the risk that changes to syncing, configuration, commands, or repository integration break existing behavior.

How iHildy/opencode-synced configures Claude Code and Codex

Reuse

Borrowing it

Nothing to install: this file belongs to iHildy/opencode-synced. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/iHildy/opencode-synced/main/.agents/skills/opencode-sync-sandbox/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/iHildy/opencode-synced

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/ihildy/opencode-synced/opencode-sync-sandbox/github.svg)](https://agentmods.dev/skills/ihildy/opencode-synced/opencode-sync-sandbox)

Your own site

<a href="https://agentmods.dev/skills/ihildy/opencode-synced/opencode-sync-sandbox"><img src="https://agentmods.dev/badge/skills/ihildy/opencode-synced/opencode-sync-sandbox/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/ihildy/opencode-synced/opencode-sync-sandbox"><img src="https://agentmods.dev/badge/skills/ihildy/opencode-synced/opencode-sync-sandbox.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 46 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 654 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits

NVIDIA SkillSpector pass 7 Sept 2026

How audits are shown

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.

Model	Per session	Once invoked
Fable 5.1	$0.00046	$0.00654
Opus 5.5	$0.00018	$0.00262
Sonnet 5.5	$0.00009	$0.00131
Haiku 4.5	$0.00005	$0.00065

Measured 2mo ago against content hash 7f2265bb6d4d, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

opencode-sync-sandbox 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 2mo ago.

The scan reads SKILL.md. This mod also ships 2 executable files (scripts/preflight.sh, scripts/run-e2e.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

.agents/skills/opencode-sync-sandbox/SKILL.md · 65 lines

How it starts

The opening of the file, as written. The whole thing — 65 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Opencode Sync Sandbox

Follow this workflow whenever a task changes sync behavior, config handling, command behavior, or repo/GitHub integration.

Required Workflow

Create a concrete plan before editing files.
Spawn as many subagents as useful for parallelizable work (tests, refactors, docs, investigations).
Implement the change in small, reviewable steps.
Add or update unit/regression tests for the behavior you changed.
Run local checks:
- bun run check
- bun test
- bun run build
Run full isolated E2E before declaring success:
- ./.agents/skills/opencode-sync-sandbox/scripts/run-e2e.sh
- Run E2E variants that directly exercise the features changed in this task (for example: sessions, secrets, or other changed sync flags/paths).
Report exact evidence: what changed, what tests ran, and an E2E artifact review.

Do not skip E2E for changes that affect sync workflows, path resolution, repo operations, or command execution.

E2E Reporting Requirements

Do not report the E2E artifact path unless the user explicitly asks for it.
Read results/summary.json, command result payloads under results/, and relevant logs/*.log tails.
Summarize the executed flow, pass/fail status, key warnings/errors, and any suspicious signals.
If warnings exist, explain whether they are expected, tolerated, or need follow-up.
For feature-flagged runs, report the exact artifact-level behavior for each changed feature (including restart requirements when relevant).

Sandbox Rules

Keep all E2E state inside .memory/e2e/runs/<run-id>/.
Never rely on shared global opencode directories for E2E assertions.
Use the harness-created isolated HOME/XDG sandboxes for each instance.
Use ephemeral GitHub repos for test runs; keep failed repos only when debugging is needed.

Upstream Reference Rule

Before changing integration-sensitive behavior, inspect upstream opencode source in:

.memory/opencode-upstream/opencode

Use this clone to confirm command/server/tool behavior and avoid assumptions.

Read the full file on GitHub · 65 lines

Files

What ships with it

3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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.

2mo ago First seen · 65 lines · 46 tokens per session scan A 7f2265bb6d4d

Subscribe to this mod's changes

opencode-sync-sandbox is a skill published in the GitHub repository iHildy/opencode-synced (168 stars, last pushed 1mo ago), licensed MIT. It adds 46 tokens to every session and 654 once invoked, about $0.0002 per session on Opus 5.5. 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.

opencode-sync-sandbox next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
opencode-sync-sandboxiHildy/opencode-synced	Skill	168	1mo ago	MIT	A	46	Claude Code, Codex
imagegenopenai/codex	Skill	134k	today	Apache-2.0	A	113	Codex
local-ai-agentsmicrosoft/ai-agents-for-beginners	Skill	79k	yesterday	MIT	A	200	Claude Code, Codex
playwright-climicrosoft/playwright	Skill	100k	yesterday	Apache-2.0	A	19	Claude Code
browser-automationopenclaw/openclaw	Skill	394k	today	MIT	A	36	Claude Code
systematic-debuggingobra/superpowers	Skill	314k	4d ago	MIT	A	21	Claude Code
next-cache-components-adoptionvercel/next.js	Skill	143k	today	MIT	A	95	Claude Code

opencode-synced: Skill for Claude Code