## Thinking Path
> - Paperclip is the open source control plane people use to manage AI
agents for work.
> - Local coding adapters currently spawn their CLI processes directly
on the Paperclip host.
> - CLI-native approval and sandbox flags do not provide a reliable host
filesystem or network boundary.
> - An agent can therefore inspect unrelated host files or fetch
external material when an operator needs stronger isolation.
> - The confinement must stay opt-in so existing local adapter behavior
does not change unexpectedly.
> - This pull request adds a shared Linux Bubblewrap spawn layer for
workspace filesystem and deny/allowlist network scopes.
> - The benefit is enforceable defense in depth around Codex and Claude
local runs while preserving explicit provider connectivity.
## Linked Issues or Issue Description
### What happened?
`codex_local` and `claude_local` processes could read arbitrary host
paths and make unrestricted outbound network requests because Paperclip
did not impose a spawn-level boundary.
### Expected behavior
Operators can opt into a workspace-only filesystem view and either deny
network egress or allow exact provider/API hosts, independently of CLI
approval flags.
### Steps to reproduce
1. Run current `master` on Linux and configure a Codex or Claude local
adapter.
2. Ask the agent to read a canary file outside its active workspace.
3. Ask the agent to `curl` a public host.
4. Observe that both operations succeed without a Paperclip-level
confinement option.
### Environment
- Paperclip commit: `c36f1a4af` / current `master` base.
- Deployment mode: Linux local dev or self-hosted server.
- Installation: built from source.
- Adapters: Codex and Claude Code.
- Database: not related.
## What Changed
- Added a shared Bubblewrap process wrapper with opt-in
`filesystemScope: "workspace"`, managed/extra path mounts, private
`/tmp`, and Linux-only validation.
- Added `networkScope: "deny" | "allowlist"`; both use a private network
namespace, while allowlist mode exposes an exact-host HTTP(S) proxy over
a Unix-socket bridge.
- Wired Codex and Claude local CLI execution through the wrapper and
forced scoped auto runs onto the CLI lane because ACP processes are not
covered.
- Added unit and gated Bubblewrap canaries for outside-file denial,
workspace writes, direct network denial, allowlisted forwarding, and
rejected destinations.
- Documented both scopes, provider allowlist examples, Bubblewrap
requirements, and default-off behavior.
## Verification
- `pnpm exec vitest run
packages/adapter-utils/src/local-process-sandbox.test.ts
packages/adapters/codex-local/src/server/acp.test.ts
packages/adapters/claude-local/src/server/acp.test.ts` — 34 passed, 4
gated Bubblewrap tests skipped by default.
- `pnpm --filter @paperclipai/adapter-utils typecheck`
- `pnpm --filter @paperclipai/adapter-codex-local typecheck`
- `pnpm --filter @paperclipai/adapter-claude-local typecheck`
- `pnpm --filter @paperclipai/adapter-utils build`
- `pnpm --filter @paperclipai/adapter-codex-local build`
- `pnpm --filter @paperclipai/adapter-claude-local build`
- Attempted the gated tests with a vendored Bubblewrap binary; this
container blocks unprivileged namespace setup (`setting up uid map:
Permission denied` / loopback `RTM_NEWADDR: Operation not permitted`),
so kernel-level execution remains for CI or a namespace-enabled Linux
host.
## Risks
- Bubblewrap must be installed and unprivileged user/mount/network
namespaces must be enabled on the host; scoped runs fail clearly if the
prerequisite is missing.
- Allowlist mode depends on the coding CLI honoring standard
`HTTP_PROXY` / `HTTPS_PROXY` variables; custom providers must list every
required exact hostname and port.
- Exact-host allowlists intentionally reject wildcards, which is safer
but may require operators to enumerate multi-host provider setups.
- No behavior changes unless an operator enables `filesystemScope` or
`networkScope`.
> This aligns with the ROADMAP direction toward safer remote and
sandboxed agent environments and does not duplicate an open PR or issue
found in the repository search.
## Model Used
- OpenAI GPT-5.5 (`gpt-5.5`) via Codex CLI, with reasoning, repository
tool use, shell execution, code editing, and test execution. The serving
context-window size is not exposed to the agent.
## Checklist
- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have searched GitHub for duplicate or related PRs and linked
them above
- [x] I have either (a) linked existing issues with `Fixes: #` / `Closes
#` / `Refs #` OR (b) described the issue in-PR following the relevant
issue template
- [x] I have not referenced internal/instance-local Paperclip issues or
links (only public GitHub `#NNN` / `github.com/paperclipai/paperclip`
URLs)
- [x] My branch name describes the change (e.g. `docs/...`, `fix/...`)
and contains no internal Paperclip ticket id or instance-derived details
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [ ] All Paperclip CI gates are green
- [ ] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I will address all Greptile and reviewer comments before
requesting merge
---------
Co-authored-by: Paperclip <noreply@paperclip.ing>