fix(kimi-inspect): the sync's prompt-channel import pulls node:path into the browser bundle and breaks `pnpm run build`

[arrrrny]

pnpm run build fails in apps/kimi-inspect on the 2026-09-14 upstream sync. It is the only red check on the sync PR: lint, typecheck, test (1)–test (5), test-pi-tui, test-vscode-legacy, nix build .#kimi-code and the flake sync check all pass.

Failure

CI: https://github.com/arrrrny/kimi-code-sync/actions/runs/34935202474/job/104271512860

apps/kimi-inspect build: error during build:
../../packages/agent-core-v2/src/agent/media/mediaRef.ts (1:9): "join" is not exported by "__vite-browser-external",
imported by "../../packages/agent-core-v2/src/agent/media/mediaRef.ts".
1: import { join } from 'node:path';

apps/kimi-inspect is a browser app bundled by vite, so node:path is externalized and the named join import cannot resolve.

Root cause

apps/kimi-inspect/src/components/ChatView.tsx:28 takes a runtime import of an engine token:

import { IAgentPromptChannel } from '@moonshot-ai/agent-core-v2/agent/loop/promptChannel';

used as a DI token at ChatView.tsx:382 (.service(IAgentPromptChannel).submit(...)), so the module is genuinely bundled. That module is heavy at runtime — unlike a plain token module, it also declares the implementation class:

• packages/agent-core-v2/src/agent/loop/promptChannel.ts:26 — createDecorator<IAgentPromptChannel>('agentPromptService'), plus value imports of #/session/agentLifecycle/agentLifecycle (MAIN_AGENT_ID), #/session/sessionContext/sessionContext, #/session/sessionMetadata/sessionMetadata, #/session/sessionMetadata/promptMetadata, #/agent/prompt/promptMetadataText, #/app/event/event, #/app/telemetry/telemetry and ./loop.
• That graph reaches packages/agent-core-v2/src/agent/loop/loopService.ts:37 (daemonFileRefFromPart from #/agent/media/mediaRef), and mediaRef.ts:1 is import { join } from 'node:path'.
• apps/kimi-inspect/vite.config.ts has no node:* shim, so this surfaces as a build error rather than a runtime one.

Why this is new in this sync

On master the same call site imported a type-only-heavy module:

• apps/kimi-inspect/src/components/ChatView.tsx (master) — import { IAgentPromptService } from '@moonshot-ai/agent-core-v2/agent/prompt/prompt'.
• packages/agent-core-v2/src/agent/prompt/prompt.ts (master) had exactly one runtime import (createDecorator); everything else — including #/agent/loop/loop — was import type, so almost the whole module was erased from the browser bundle.

Upstream's prompt-queue fold (upstream PR MoonshotAI#3747) deleted agent/prompt/prompt.ts, and the sync's review-fix commit 106192eb5 repointed the import to promptChannel.ts. That is the change that pulls the session graph, and node:path, into the bundle.

Not a conflict-resolution mistake: the old module no longer exists, so the import had to move somewhere. The new home is simply not browser-safe.

What needs to be fixed

Keep the token reference but stop importing the heavy module. The app already has the right pattern: apps/kimi-inspect/src/channel/channels.ts:15 imports createDecorator from the light @moonshot-ai/agent-core-v2/_base/di/instantiation, and channel/client.ts documents that "the decorator id (String(id)) is the channel name" — klient's channel layer routes by service-name string (packages/klient/src/core/channel.ts), and the engine token's id is the wire name agentPromptService.

Proposed change, confined to the fork's own app:

import type { IAgentPromptChannel as PromptChannel } from '@moonshot-ai/agent-core-v2/agent/loop/promptChannel';
import { createDecorator } from '@moonshot-ai/agent-core-v2/_base/di/instantiation';

const IAgentPromptChannel = createDecorator<PromptChannel>('agentPromptService');

import type is erased at build time, so only the light createDecorator module stays in the bundle.

Alternative (weigh against sync conflicts): move just the interface + decorator out of promptChannel.ts into a light token module in the engine, leaving the class behind. Structurally cleaner, but it diverges in an upstream-owned area and will conflict on every future sync.

Please do not fix this by aliasing or stubbing node:path in apps/kimi-inspect/vite.config.ts: that would silently let Node-only code paths into the browser bundle instead of keeping the import graph browser-safe.

Verification notes

• Reproduce with the full workspace build (pnpm -r build from the repo root) — apps/kimi-inspect alone fails earlier with Rollup failed to resolve import "@moonshot-ai/kap-server/protocol" from apps/kimi-inspect/src/transcript/api.ts, because sibling packages must be built first. That earlier error is an artifact of building the app in isolation, not a second bug.
• After the fix, confirm the bundle builds and that the prompt composer still submits: the token id must stay agentPromptService, since that string is what the RPC routes on.

References

• Sync PR: chore: sync upstream 2026-09-14 #81 (do not merge until this is fixed)
• Sync conflict issue: sync: upstream merge conflicts require manual resolution #80
• Import repoint: commit 106192eb5 (fix: address review comments on #81)
• Upstream removal: commit 46233953795c (upstream PR refactor(agent-core-v2): fold the prompt queue into the agent loop service MoonshotAI/kimi-code#3747)