## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work.
> - First-party **plugins** run as isolated workers spawned by the host
`plugin-loader`, reading company-scoped config through a governed
`ctx.config.get(companyId)` channel.
> - The host→worker `configChanged` RPC carries `{ config, companyId }`,
but the SDK dispatch dropped the scope — `onConfigChanged(newConfig)`
was companyId-blind by design — so a **proactive** worker kept a single
worker-global config.
> - #10092 added a startup replay that fans out **every** stored
company's config through `configChanged`. With no deterministic
ordering, a plugin configured for more than one distinct company ends up
running as whichever DB row was delivered last.
> - That is a latent cross-tenant identity/secret confusion bug: one
company's bot token could be applied to another company's traffic.
> - This pull request threads `companyId` through `onConfigChanged` and
adds a fail-closed cross-tenant guard at the SDK layer, so a
single-tenant worker can never silently collapse to a second company's
config.
> - The benefit is that the config-delivery class is fixed at the SDK
boundary — before any genuinely multi-company proactive plugin ships —
without changing today's single-tenant behavior.
## Linked Issues or Issue Description
No public GitHub issue — describing in-PR (hardening / latent security):
**Latent cross-tenant config collapse.** The worker-side `configChanged`
dispatch forwarded only `config` and dropped `companyId`, so a proactive
plugin kept a single worker-global config. #10092's startup replay
delivers every configured company's config sequentially with no `ORDER
BY`, so a plugin with configs for more than one distinct company would
apply a nondeterministic last-write-wins global config (one tenant's
credential applied to another's traffic).
- Builds on and must merge after #10092.
- Not exploitable today: the only proactive consumer (the chat gateway)
has single-tenant config rows, so last-write-wins is a no-op. This is a
hardening pre-condition before any multi-company proactive plugin ships.
## What Changed
- **Thread scope through:** `onConfigChanged(newConfig, context)` with a
new exported `PluginConfigChangeContext { companyId }`. Backward
compatible — the second arg is optional; existing single-arg
implementations are unaffected.
- **Fail-closed cross-tenant guard** (`worker-rpc-host.ts`): a
single-tenant plugin that receives `configChanged` for a second,
distinct company with a *different* config is rejected with the new
`PLUGIN_RPC_ERROR_CODES.CROSS_TENANT_CONFIG` instead of silently
overwriting the applied tenant's config. Idempotent replays of the
*same* config under a different scope row remain allowed.
- **Opt-in `multiCompanyConfig: true`** on the plugin definition for
plugins that genuinely serve multiple companies from one worker (keying
per-company state on `context.companyId`); the guard is bypassed for
those.
- **Deterministic `ORDER BY companyId`** on `registry.listConfigs`, so
the startup replay binds a single-tenant worker to a stable company
across restarts.
- **Loader visibility:** a `CROSS_TENANT_CONFIG` rejection is logged at
`warn` (was best-effort `debug`) so the misconfiguration is surfaced.
- **Regression test**
(`packages/plugins/sdk/tests/worker-rpc-host.test.ts`): two distinct
companies delivered via the startup-replay path fail closed and stay
bound to the first company; an idempotent same-config replay under a
different scope row is allowed; a `multiCompanyConfig` plugin receives
per-company config with the correct `context.companyId`.
## Verification
- SDK `tsc --noEmit`: clean.
- SDK vitest `worker-rpc-host.test.ts`: 7/7 pass (incl. 3 new). The
two-distinct-company case **fails against pre-fix code** and passes
after the fix.
- #10092 embedded-postgres `plugin-config-startup-delivery.test.ts`: 3/3
pass (unaffected by the new `ORDER BY`).
- Full server `tsc --noEmit` against this SDK: clean.
## Risks
- **Low functional risk.** The second `onConfigChanged` arg is optional
and existing implementations are unchanged. Today's single-tenant
gateway keeps working — idempotent same-config replays are explicitly
allowed, so the go-live is preserved.
- **Behavioral shift on misconfig:** a genuinely multi-company plugin
that has NOT opted into `multiCompanyConfig` now fails closed
(`CROSS_TENANT_CONFIG`) rather than silently collapsing to one tenant.
This is the intended safer default; opt in with `multiCompanyConfig:
true` to serve multiple companies from one worker.
- **Not in scope (residual).** Per-company workers/connections for a
genuinely multi-company gateway increase resource use and are tracked
separately (ties into the #10092 fan-out/timeout follow-up). This PR
fixes the class and fails closed; it does not build multi-tenant
connection management.
## Model Used
Claude — Anthropic `claude-opus-4-8` (Opus 4.8), extended thinking, with
tool use / code execution via Claude Code.
## 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)
- [ ] My branch name describes the change and contains no internal
Paperclip ticket id — branch predates this rule; not renaming an open PR
mid-review
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [ ] I have updated relevant documentation to reflect my changes — no
doc surface; internal SDK/host behavior only
- [x] I have considered and documented any risks above
- [x] All Paperclip CI gates are green
- [x] I will address all Greptile and reviewer comments before
requesting merge
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: anicca <annica@Michaels-Mac-Studio.local>
Co-authored-by: Paperclip <noreply@paperclip.ing>
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