Run harness adapters (Claude Code, Codex, OpenCode) INSIDE isolated sandboxes via defineSandbox + withSandbox + a provider (localProcessSandbox / dockerSandbox). Covers declarative provisioning: createSecrets + secret/bearer, skills (agentSkill/gitSkill/mcpSkill/ fileSkill), plugins, instructions → canonical AGENTS.md + symlinks projected per harness; shallow-clone default with depth opt-out; serial/parallel setup callback over a persistent shell; snapshot-after-setup default with snapshotMaxAge TTL; defineWorkspace (git/setup/scripts/skills/secrets/ instructions/plugins), defineSandboxPolicy (allow/ask/deny), lifecycle/resume, the SandboxHandle (fs/git/process/ports), capability tokens, defineSandbox hooks (onFile/onFileCreate/onFileChange/onFileDelete/onReady/onError/ onDestroy) + fileEvents flag, chat middleware sandbox group (defineChatMiddleware sandbox hooks), the sandbox debug category, watchWorkspace as a low-level building block, the file.changed / sandbox.file / claude-code.session-id events, and the run journal (spawnNdjson journal option, runId uniqueness, follow vs bounded-poll reading, alignToStoredLog replay alignment, chunkFingerprint, createRunScopedIdGen), and takeover of detached runs (withSandbox runs+durability as one opt-in, detach vs cancel via requestRunCancel / RUN_CANCEL_REASON, sandboxRunDriver on the resume path, single-writer fencing of BOTH the event log and the run record, replay-from-zero with JournalReplayDivergedError, the distributed LockStore requirement). Use whenever a harness adapter needs a sandbox or when building sandbox providers.
Security
1 medium severity finding. This skill can be installed but you should review these findings before use.
The skill prompts the agent to compromise the security or integrity of the user’s machine by modifying system-level services or configurations, such as obtaining elevated privileges, altering startup scripts, or changing system-wide settings.
The document explicitly recommends using sudo in provider setup ("must use `sudo -n`") and exposes non-isolated host execution (`localProcessSandbox()`), which encourages elevated or host-modifying operations, but it does not instruct the agent to create users, edit systemctl/ssh configs, or actively bypass security—so the risk is present but limited.
Low
Low-risk findings.
1 low severity finding. Worth noting, but not necessarily harmful.
The skill fetches instructions or code from an external URL at runtime, and the fetched content directly controls the agent’s prompts or executes code. This dynamic dependency allows the external source to modify the agent’s behavior without any changes to the skill itself.
The workspace source "https://github.com/owner/repo" is cloned into the sandbox at runtime (defineWorkspace.source) and the sandbox runs setup commands there (e.g., pnpm install / pnpm test), so the fetched repo content can directly control agent context/prompts and cause remote-executed code to run.
2822885
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