feat: serve mcp backed rpc server

docs/superpowers/plans/2026-06-04-rpc-server-mcp-config-hookup.md

@@ -0,0 +1,435 @@
+# RPC Server MCP Config Hookup Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Let `wf-rpc-server` serve a real MCP-backed `WorkflowServer` from an MCP broker config file, so `wf --url ...` can target a long-lived server with MCP sources and source-registry/admin surfaces.
+
+**Architecture:** Keep JSON-RPC transport code as the place that selects a server composition for the process. `--mcp-config` loads legacy MCP broker config and calls `wf_mcp.broker.build_workflow_server_from_config`; existing `--store-root` / neutral `--config` behavior continues to build the local/static server. The transport still receives only a neutral `WorkflowServer` and calls `create_rpc_app(server)`.
+
+**Tech Stack:** Python 3.14, Typer, `wf_transport_rpc_http`, `wf_mcp.broker`, `wf_server`, pytest, ruff, basedpyright.
+
+---
+
+## Current Context
+
+Implemented before this plan:
+
+- `wf_mcp.broker.server.build_workflow_server_from_config(config)` returns a neutral `WorkflowServer`.
+- `wf_transport_rpc_http.cli.serve()` currently always calls `build_local_static_workflow_server(...)`.
+- Existing CLI tests in `tests/wf_transport_rpc_http/test_cli.py` monkeypatch server construction, `create_rpc_app`, and `uvicorn.run`; use that pattern.
+
+Out of scope:
+
+- No new neutral config schema for MCP source transports.
+- No server hot reload.
+- No process manager/daemon work.
+- No auth redesign.
+- No real socket startup in tests.
+
+---
+
+## File Structure
+
+- Modify `src/wf_transport_rpc_http/cli.py`
+  - Add `--mcp-config`.
+  - Select MCP-backed server when `--mcp-config` is supplied.
+  - Keep local/static path unchanged for existing config/store-root flows.
+- Modify `tests/wf_transport_rpc_http/test_cli.py`
+  - Add help assertion for `--mcp-config`.
+  - Add server-selection tests.
+- Modify `docs/wf_cli.md`
+  - Document local/static server and MCP-backed server startup examples.
+- Modify `docs/current_roadmap.md`
+  - Mark RPC server CLI MCP config hookup complete.
+- Modify `docs/superpowers/specs/2026-06-03-long-lived-workflow-api-boundary.md`
+  - Record Slice 5 status.
+
+---
+
+### Task 1: Add MCP Config Server Selection to RPC CLI
+
+**Files:**
+- Modify: `src/wf_transport_rpc_http/cli.py`
+- Modify: `tests/wf_transport_rpc_http/test_cli.py`
+
+- [ ] **Step 1: Add failing help and selection tests**
+
+In `tests/wf_transport_rpc_http/test_cli.py`, update `test_rpc_server_cli_help_mentions_store_root`:
+
+```python
+def test_rpc_server_cli_help_mentions_store_root() -> None:
+    result = CliRunner().invoke(app, ["--help"])
+
+    assert result.exit_code == 0
+    assert "--store-root" in result.output
+    assert "--mcp-config" in result.output
+    assert "--host" in result.output
+    assert "--port" in result.output
+```
+
+Add:
+
+```python
+def test_rpc_server_cli_uses_mcp_config_server(monkeypatch, tmp_path) -> None:
+    config_path = tmp_path / "wf_mcp.config.json"
+    config_path.write_text(
+        json.dumps(
+            {
+                "store_root": str(tmp_path / "store"),
+                "connections": [],
+            }
+        ),
+        encoding="utf-8",
+    )
+    captured: dict[str, object] = {}
+
+    def fake_load_broker_config(path):
+        captured["mcp_config_path"] = path
+        return "broker-config"
+
+    def fake_build_mcp_server(config):
+        captured["mcp_config"] = config
+        return object()
+
+    def fake_create_rpc_app(server, *, rpc_path="/rpc"):
+        captured["server"] = server
+        captured["rpc_path"] = rpc_path
+        return object()
+
+    def fake_uvicorn_run(app_obj, *, host, port, access_log):
+        captured["app"] = app_obj
+        captured["host"] = host
+        captured["port"] = port
+        captured["access_log"] = access_log
+
+    monkeypatch.setattr("wf_transport_rpc_http.cli.load_broker_config", fake_load_broker_config)
+    monkeypatch.setattr(
+        "wf_transport_rpc_http.cli.build_workflow_server_from_config",
+        fake_build_mcp_server,
+    )
+    monkeypatch.setattr("wf_transport_rpc_http.cli.create_rpc_app", fake_create_rpc_app)
+    monkeypatch.setattr("wf_transport_rpc_http.cli.uvicorn.run", fake_uvicorn_run)
+
+    result = CliRunner().invoke(
+        app,
+        [
+            "--mcp-config",
+            str(config_path),
+            "--host",
+            "127.0.0.9",
+            "--port",
+            "9988",
+        ],
+    )
+
+    assert result.exit_code == 0, result.output
+    assert captured["mcp_config_path"] == config_path
+    assert captured["mcp_config"] == "broker-config"
+    assert captured["server"] is not None
+    assert captured["rpc_path"] == "/rpc"
+    assert captured["host"] == "127.0.0.9"
+    assert captured["port"] == 9988
+    assert captured["access_log"] is False
+```
+
+Add conflict test:
+
+```python
+def test_rpc_server_cli_rejects_mcp_config_with_store_root(tmp_path) -> None:
+    config_path = tmp_path / "wf_mcp.config.json"
+    config_path.write_text(
+        json.dumps({"store_root": str(tmp_path / "store"), "connections": []}),
+        encoding="utf-8",
+    )
+
+    result = CliRunner().invoke(
+        app,
+        [
+            "--mcp-config",
+            str(config_path),
+            "--store-root",
+            str(tmp_path / "other"),
+        ],
+    )
+
+    assert result.exit_code != 0
+    assert "--mcp-config cannot be combined with --store-root" in result.output
+```
+
+Run:
+
+```bash
+uv run pytest tests/wf_transport_rpc_http/test_cli.py -q
+```
+
+Expected: FAIL because `--mcp-config` is not implemented.
+
+- [ ] **Step 2: Implement `--mcp-config` option**
+
+In `src/wf_transport_rpc_http/cli.py`, import:
+
+```python
+from wf_mcp.broker import build_workflow_server_from_config, load_broker_config
+```
+
+Add option to `serve(...)`:
+
+```python
+mcp_config: Path | None = typer.Option(
+    None,
+    "--mcp-config",
+    help="Path to MCP broker config JSON for MCP-backed workflow server.",
+),
+```
+
+Update docstring:
+
+```python
+"""Serve WorkflowApi over JSON-RPC HTTP."""
+```
+
+Before resolving local/static store root, add validation:
+
+```python
+if mcp_config is not None and store_root is not None:
+    raise typer.BadParameter("--mcp-config cannot be combined with --store-root")
+```
+
+If `mcp_config` is supplied, build MCP server:
+
+```python
+server = None
+if mcp_config is not None:
+    broker_config = load_broker_config(mcp_config)
+    server = build_workflow_server_from_config(broker_config)
+```
+
+Then keep existing neutral `--config` parsing for host/port/path. When selecting
+the final server, only call `build_local_static_workflow_server(...)` if
+`server is None`:
+
+```python
+if server is None:
+    if resolved_store_root is None:
+        raise typer.BadParameter(
+            "--store-root is required when --config is not supplied"
+        )
+    server = build_local_static_workflow_server(resolved_store_root)
+```
+
+Important:
+
+- `--config` may still be used with `--mcp-config` for transport host/port/path.
+- `--mcp-config` owns the workflow server/store/source side.
+- `--store-root` is local/static-only and must conflict with `--mcp-config`.
+
+- [ ] **Step 3: Run CLI tests**
+
+Run:
+
+```bash
+uv run pytest tests/wf_transport_rpc_http/test_cli.py -q
+```
+
+Expected: PASS.
+
+- [ ] **Step 4: Commit**
+
+```bash
+git add src/wf_transport_rpc_http/cli.py tests/wf_transport_rpc_http/test_cli.py
+git commit -m "feat: serve mcp backed rpc server"
+```
+
+---
+
+### Task 2: Prove MCP Config Server Supports Registry RPC Through CLI Path
+
+**Files:**
+- Modify: `tests/wf_transport_rpc_http/test_cli.py`
+
+- [ ] **Step 1: Add integration-style construction test**
+
+Add this test to `tests/wf_transport_rpc_http/test_cli.py`:
+
+```python
+def test_rpc_server_cli_mcp_config_builds_registry_capable_server(monkeypatch, tmp_path) -> None:
+    config_path = tmp_path / "wf_mcp.config.json"
+    config_path.write_text(
+        json.dumps(
+            {
+                "store_root": str(tmp_path / "store"),
+                "connections": [],
+            }
+        ),
+        encoding="utf-8",
+    )
+    captured: dict[str, object] = {}
+
+    def fake_create_rpc_app(server, *, rpc_path="/rpc"):
+        captured["source_registry_admin"] = server.source_registry_admin
+        captured["rpc_path"] = rpc_path
+        return object()
+
+    def fake_uvicorn_run(app_obj, *, host, port, access_log):
+        captured["host"] = host
+        captured["port"] = port
+
+    monkeypatch.setattr("wf_transport_rpc_http.cli.create_rpc_app", fake_create_rpc_app)
+    monkeypatch.setattr("wf_transport_rpc_http.cli.uvicorn.run", fake_uvicorn_run)
+
+    result = CliRunner().invoke(app, ["--mcp-config", str(config_path)])
+
+    assert result.exit_code == 0, result.output
+    assert captured["source_registry_admin"] is not None
+    assert captured["rpc_path"] == "/rpc"
+    assert captured["host"] == "127.0.0.1"
+    assert captured["port"] == 8765
+```
+
+This test uses the real `load_broker_config()` and
+`build_workflow_server_from_config()` but still avoids starting uvicorn.
+
+- [ ] **Step 2: Run CLI tests**
+
+Run:
+
+```bash
+uv run pytest tests/wf_transport_rpc_http/test_cli.py -q
+```
+
+Expected: PASS.
+
+- [ ] **Step 3: Commit**
+
+```bash
+git add tests/wf_transport_rpc_http/test_cli.py
+git commit -m "test: cover mcp config rpc server path"
+```
+
+---
+
+### Task 3: Update User-Facing Docs and Roadmap
+
+**Files:**
+- Modify: `docs/wf_cli.md`
+- Modify: `docs/current_roadmap.md`
+- Modify: `docs/superpowers/specs/2026-06-03-long-lived-workflow-api-boundary.md`
+
+- [ ] **Step 1: Add RPC server startup docs**
+
+In `docs/wf_cli.md`, after the opening config paragraph, add:
+
+```markdown
+## Remote Server
+
+Start a local/static JSON-RPC workflow server:
+
+```bash
+wf-rpc-server --store-root .wf_store --host 127.0.0.1 --port 8765
+```
+
+Start a JSON-RPC server backed by MCP broker config and MCP-capable sources:
+
+```bash
+wf-rpc-server --mcp-config wf_mcp.config.json --host 127.0.0.1 --port 8765
+```
+
+Then point `wf` at it:
+
+```bash
+wf --url http://127.0.0.1:8765/rpc cap list
+wf --url http://127.0.0.1:8765/rpc admin registry list
+```
+
+`--mcp-config` owns the server's workflow stores, MCP connections, and source
+registry. `--store-root` is for the local/static server path and cannot be
+combined with `--mcp-config`.
+```
+
+- [ ] **Step 2: Update roadmap**
+
+In `docs/current_roadmap.md`, under **Durable API service shape**, add:
+
+```markdown
+   - Completed: `wf-rpc-server --mcp-config wf_mcp.config.json` starts the
+      JSON-RPC transport over an MCP-backed `WorkflowServer`, making the remote
+      CLI path usable with MCP sources and desired source registry operations.
+```
+
+- [ ] **Step 3: Update long-lived API spec**
+
+In `docs/superpowers/specs/2026-06-03-long-lived-workflow-api-boundary.md`,
+update status from "Slices 1-4 implemented" to "Slices 1-5 implemented", and
+add under implementation status:
+
+```markdown
+- Slice 5 complete: `wf-rpc-server --mcp-config <path>` starts JSON-RPC over an
+  MCP-backed `WorkflowServer`; `--store-root` remains local/static-only.
+```
+
+- [ ] **Step 4: Run docs grep**
+
+Run:
+
+```bash
+rg -n "wf-rpc-server --mcp-config|Slices 1-5 implemented|--store-root.*--mcp-config" docs/wf_cli.md docs/current_roadmap.md docs/superpowers/specs/2026-06-03-long-lived-workflow-api-boundary.md
+```
+
+Expected: all three docs mention the new server path.
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add docs/wf_cli.md docs/current_roadmap.md docs/superpowers/specs/2026-06-03-long-lived-workflow-api-boundary.md
+git commit -m "docs: document mcp backed rpc server"
+```
+
+---
+
+### Task 4: Final Verification
+
+**Files:**
+- Verify only.
+
+- [ ] **Step 1: Run focused tests**
+
+Run:
+
+```bash
+uv run pytest tests/wf_transport_rpc_http/test_cli.py tests/wf_transport_rpc_http/test_mcp_backed_server_rpc.py tests/wf_mcp/test_mcp_workflow_server.py -q
+```
+
+Expected: all tests pass.
+
+- [ ] **Step 2: Run lint and type checks**
+
+Run:
+
+```bash
+uv run ruff check src/wf_transport_rpc_http/cli.py tests/wf_transport_rpc_http/test_cli.py
+uv run basedpyright --level error src/wf_transport_rpc_http/cli.py tests/wf_transport_rpc_http/test_cli.py
+git diff --check
+```
+
+Expected: all commands exit 0. CRLF warnings from Git are acceptable; whitespace
+errors are not.
+
+- [ ] **Step 3: Final report**
+
+Report:
+
+- changed files
+- verification output
+- exact command a user can run for MCP-backed RPC server
+- any deviations from this plan
+
+Do not run the full suite unless the focused verification is green.
+
+---
+
+## Self-Review
+
+- Product fit: this is the smallest visible hook after MCP-backed `WorkflowServer` construction.
+- Boundary: `wf_transport_rpc_http.cli` imports `wf_mcp.broker` only for process startup selection; JSON-RPC app/method modules still take a neutral `WorkflowServer`.
+- Config semantics: `--mcp-config` and `--store-root` conflict because they own different server composition paths.
+- Testing: no real socket startup; tests monkeypatch `uvicorn.run`.

src/wf_transport_rpc_http/cli.py

@@ -11,6 +11,8 @@ from wf_config import (
     load_workflow_config,
 )
 
+from wf_mcp.broker import build_workflow_server_from_config, load_broker_config
+
 from wf_server import build_local_static_workflow_server
 
 from .app import create_rpc_app
@@ -30,6 +32,11 @@ def serve(
         "--store-root",
         help="Override filesystem workflow store root.",
     ),
+    mcp_config: Path | None = typer.Option(
+        None,
+        "--mcp-config",
+        help="Path to MCP broker config JSON for MCP-backed workflow server.",
+    ),
     host: str | None = typer.Option(
         None,
         "--host",
@@ -43,11 +50,20 @@ def serve(
         help="Override RPC bind port; defaults to config or 8765.",
     ),
 ) -> None:
-    """Serve the local/static WorkflowApi over JSON-RPC HTTP."""
+    """Serve WorkflowApi over JSON-RPC HTTP."""
+    if mcp_config is not None and store_root is not None:
+        raise typer.BadParameter("--mcp-config cannot be combined with --store-root")
+
     resolved_store_root = store_root
     resolved_host = host
     resolved_port = port
     resolved_rpc_path = "/rpc"
+
+    server = None
+    if mcp_config is not None:
+        broker_config = load_broker_config(mcp_config)
+        server = build_workflow_server_from_config(broker_config)
+
     if config is not None:
         workflow_config = load_workflow_config(config)
         store = workflow_config.server.store
@@ -68,12 +84,14 @@ def serve(
             resolved_host = host or rpc_transport.host
             resolved_port = port or rpc_transport.port
             resolved_rpc_path = rpc_transport.path
+
+    if server is None:
         if resolved_store_root is None:
             raise typer.BadParameter(
                 "--store-root is required when --config is not supplied"
             )
-
         server = build_local_static_workflow_server(resolved_store_root)
+
     rpc_app = create_rpc_app(server, rpc_path=resolved_rpc_path)
     uvicorn.run(
         rpc_app,

tests/wf_transport_rpc_http/test_cli.py

@@ -12,6 +12,7 @@ def test_rpc_server_cli_help_mentions_store_root() -> None:
 
     assert result.exit_code == 0
     assert "--store-root" in result.output
+    assert "--mcp-config" in result.output
     assert "--host" in result.output
     assert "--port" in result.output
 
@@ -99,3 +100,86 @@ def test_rpc_server_cli_uses_configured_store_and_transport(
     assert captured["host"] == "127.0.0.2"
     assert captured["port"] == 9999
     assert captured["access_log"] is False
+
+
+def test_rpc_server_cli_uses_mcp_config_server(monkeypatch, tmp_path) -> None:
+    config_path = tmp_path / "wf_mcp.config.json"
+    config_path.write_text(
+        json.dumps(
+            {
+                "store_root": str(tmp_path / "store"),
+                "connections": [],
+            }
+        ),
+        encoding="utf-8",
+    )
+    captured: dict[str, object] = {}
+
+    def fake_load_broker_config(path):
+        captured["mcp_config_path"] = path
+        return "broker-config"
+
+    def fake_build_mcp_server(config):
+        captured["mcp_config"] = config
+        return object()
+
+    def fake_create_rpc_app(server, *, rpc_path="/rpc"):
+        captured["server"] = server
+        captured["rpc_path"] = rpc_path
+        return object()
+
+    def fake_uvicorn_run(app_obj, *, host, port, access_log):
+        captured["app"] = app_obj
+        captured["host"] = host
+        captured["port"] = port
+        captured["access_log"] = access_log
+
+    monkeypatch.setattr("wf_transport_rpc_http.cli.load_broker_config", fake_load_broker_config)
+    monkeypatch.setattr(
+        "wf_transport_rpc_http.cli.build_workflow_server_from_config",
+        fake_build_mcp_server,
+    )
+    monkeypatch.setattr("wf_transport_rpc_http.cli.create_rpc_app", fake_create_rpc_app)
+    monkeypatch.setattr("wf_transport_rpc_http.cli.uvicorn.run", fake_uvicorn_run)
+
+    result = CliRunner().invoke(
+        app,
+        [
+            "--mcp-config",
+            str(config_path),
+            "--host",
+            "127.0.0.9",
+            "--port",
+            "9988",
+        ],
+    )
+
+    assert result.exit_code == 0, result.output
+    assert captured["mcp_config_path"] == config_path
+    assert captured["mcp_config"] == "broker-config"
+    assert captured["server"] is not None
+    assert captured["rpc_path"] == "/rpc"
+    assert captured["host"] == "127.0.0.9"
+    assert captured["port"] == 9988
+    assert captured["access_log"] is False
+
+
+def test_rpc_server_cli_rejects_mcp_config_with_store_root(tmp_path) -> None:
+    config_path = tmp_path / "wf_mcp.config.json"
+    config_path.write_text(
+        json.dumps({"store_root": str(tmp_path / "store"), "connections": []}),
+        encoding="utf-8",
+    )
+
+    result = CliRunner().invoke(
+        app,
+        [
+            "--mcp-config",
+            str(config_path),
+            "--store-root",
+            str(tmp_path / "other"),
+        ],
+    )
+
+    assert result.exit_code != 0
+    assert "--mcp-config cannot be combined with --store-root" in result.output