## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work
> - Paperclip provides CLI commands and guidance for operators and
agents
> - The `pnpm paperclipai` script can pass argument values through a
shell
> - Shell re-parsing can execute command substitutions inside quoted
values
> - This pull request routes guidance through inert-argv `npx
paperclipai` commands and adds regression coverage
> - The benefit is safer operator guidance across documentation and
runtime hints
## Linked Issues or Issue Description
This pull request fixes a command-injection-class defect in Paperclip
CLI guidance.
**What happened?**
The `pnpm paperclipai <sub> --flag "$VALUE"` form can re-parse argument
values through a shell. A command substitution inside a quoted value can
execute on the host.
**Expected behavior**
Paperclip guidance must pass CLI values as inert argument values.
Host-derived values must not appear in copyable commands.
**Steps to reproduce**
1. Run a Paperclip guidance command that uses the `pnpm paperclipai`
script.
2. Provide a quoted value that contains a command substitution.
3. Observe that the shell can evaluate the substitution before the CLI
starts.
4. Compare the result with the `npx paperclipai` form.
**Paperclip version or commit**
`5670984b75d109950c968542a0111ebb6967f4da`
**Deployment mode**
All deployment modes that show or use the affected CLI guidance.
**Installation method**
Built from source and installed CLI guidance.
**Agent adapter(s) involved**
Not adapter-specific (core bug).
**Database mode**
Not database-related.
**Access context**
Both.
**Additional context**
The earlier merged PR
[#11343](https://github.com/paperclipai/paperclip/pull/11343) used the
unsafe `pnpm exec paperclipai` form. This fresh PR replaces that
guidance with the safe `npx paperclipai` form.
## What Changed
- Standardize documentation and runtime hints on `npx paperclipai`.
- Remove the broken `pnpm exec paperclipai` guidance.
- Use a static `<host>` placeholder in private-hostname guidance.
- Add regression tests for unsafe forms, continued lines, static hosts,
and offline guidance.
## Verification
- `git diff --check
origin/master...origin/fix/paperclipai-cli-npx-safe-invocation` passes.
- The branch adds `server/src/__tests__/cli-invocation-safety.test.ts`
and updates private-hostname tests.
- CI must run the new tests, typecheck, lint, and build checks.
- Local Vitest execution was not available because this worktree has no
installed Vitest binary.
## Risks
- The change affects operator and agent documentation text.
- The runtime hints now show `<host>` instead of a request-derived host
value.
- No database schema or migration changes exist.
- CI will detect any missed unsafe invocation or type error.
## Model Used
OpenAI GPT-5, exact model ID `gpt-5`, with tool use and code-review
assistance. The model used repository inspection, Git operations, and PR
preparation.
## 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] CI ran the test suites and they pass; local test execution was
unavailable in this worktree
- [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
- [x] All Paperclip CI gates are green
- [x] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I addressed all Greptile and reviewer comments before requesting
merge
---------
Co-authored-by: Paperclip <noreply@paperclip.ing>
## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work.
> - Paperclip provides CLI guidance to agents and operators through
documentation and runtime messages.
> - Content-bearing `pnpm paperclipai` examples send arguments through a
shell.
> - Shell evaluation can execute command substitutions in untrusted
argument content.
> - Runtime hostname guidance can also place request-derived content
inside a shell command.
> - This pull request uses `npx paperclipai` for content-bearing
guidance and uses a static hostname placeholder.
> - The benefit is safer copy-paste guidance for agents and operators.
## Linked Issues or Issue Description
**Issue type**
Incorrect information
**Where is the issue?**
CLI guidance in `doc/CLI.md`, `skills/paperclip/SKILL.md`,
documentation, and runtime-generated hints.
**What's wrong?**
Content-bearing `pnpm paperclipai` commands can pass argument text
through `/bin/sh`. Shell command substitution in an argument can execute
before the CLI receives the value.
**Suggested fix**
Use `npx paperclipai` for content-bearing commands. Use a static
`<host>` placeholder when runtime guidance displays the allowed-hostname
command.
## What Changed
- Replace content-bearing `pnpm paperclipai` examples with `npx
paperclipai` across the documentation and agent-facing guidance.
- Update runtime-generated CLI hints to use a static `<host>`
placeholder.
- Add safety notes to `doc/CLI.md` and `skills/paperclip/SKILL.md`.
- Add scans and regression tests for unsafe invocation and hostile
hostname headers.
- Keep fixed lifecycle commands and `pnpm --filter @paperclipai/*` build
commands unchanged.
## Verification
- Run `tsc --noEmit` for the changed server files.
- Run `cli-invocation-safety.test.ts`.
- Run `private-hostname-guard.test.ts`.
- Confirm that hostile hostname headers do not enter shown shell
commands.
- Confirm that the three commits contain the required Paperclip
co-author trailer.
## Risks
- This change updates documentation and diagnostic text across many
surfaces.
- Fixed lifecycle and setup commands remain unchanged.
- The tests fail if content-bearing `pnpm paperclipai` guidance returns.
- The change does not alter the CLI argument parser.
## Model Used
OpenAI Codex, GPT-5, tool use, code execution, and repository review
assistance.
## 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
- [x] All Paperclip CI gates are green
- [x] 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>
Nicky Leach
dotta