Give the SDK JSON-RPC server a per-root tool filter and let deployments mark the configured persona as the complete system prompt. The checked-in minimal overlay now names only bash and str_replace_editor, so later global tools and unrelated guidance from dsh-base cannot appear implicitly.
Keep the shared SDK host services and packaged Web capability intact. Only workspace instructions, compaction, and the conflicting one-shot Bash row remain disabled. Unit coverage pins the configuration paths, and a real dsh profile smoke proves the assembled prompt and exact two-tool request.
Replace the TypeScript SDK's public arbitrary command/argv launch surface with the same-version dsh CLI, a named profile, ordered per-launch patches, optional process cwd, and explicit Harness home selection. Installed consumers use the built CLI; clean source checkouts use the package's src/bin.ts through an absolute tsx/esm loader and a source-only patch that omits build-generated Typert loading.
Materialize explicit or inherited environments at spawn time, keep profile-internal patches below caller patches, and resolve every caller-relative path before the child starts. The SDK subagent provider validates its optional CLI and patch files at plugin load and requires an isolated absolute child home.
Treat JSON-RPC initialize as the Loader-owned readiness point: Loader settlement joins entry imports, fiber lifecycle work, and synchronous effect registration, so the server needs no scheduler tick. A delayed profile entry registers a private adapter before initialize resolves, proving caller-supplied plugin routes are visible without fallback.
Update sdk-app ownership, server diagnostics, TypeScript SDK examples, nested-loader coverage, and session-upload replay layering together. The following commit contains only the regenerated SDK transcripts, keeping this API and lifecycle change directly reviewable.