feat(mcp): register loopover_check_improvement_potential stdio tool (#7963)

* feat(mcp): register loopover_check_improvement_potential stdio tool

* fix(test): pin MCP stdio tool count at 93 after main merge

---------

Co-authored-by: Andriy Polanski <andriy.polanski@gmail.com>

Author: andriypolanski

packages/loopover-mcp/bin/loopover-mcp.ts

@@ -720,6 +720,42 @@ const checkSlopRiskShape = {
   testFiles: z.array(z.string().max(400)).max(2000).optional(),
 };
 
+// #7759: mirrors checkImprovementPotentialShape in src/mcp/server.ts — same optional local-metadata fields the
+// CLI / REST route already accept. Stdio proxies POST /v1/lint/improvement-potential (builders stay app-side).
+const checkImprovementPotentialShape = {
+  changedFiles: z
+    .array(z.object({ path: z.string().min(1).max(400), additions: z.number().int().min(0).optional(), deletions: z.number().int().min(0).optional() }))
+    .max(2000)
+    .optional(),
+  tests: z.array(z.string().max(400)).max(2000).optional(),
+  testFiles: z.array(z.string().max(400)).max(2000).optional(),
+  patchCoverageDeltaPercent: z.number().optional(),
+  complexityDeltas: z
+    .array(
+      z.object({
+        file: z.string().min(1).max(400),
+        line: z.number().int().min(1),
+        name: z.string().min(1).max(400),
+        before: z.number().int().min(0),
+        after: z.number().int().min(0),
+        delta: z.number().int(),
+      }),
+    )
+    .max(2000)
+    .optional(),
+  duplicationDeltas: z
+    .array(
+      z.object({
+        file: z.string().min(1).max(400),
+        line: z.number().int().min(1),
+        duplicateOfLine: z.number().int().min(1),
+        lines: z.number().int().min(1),
+      }),
+    )
+    .max(2000)
+    .optional(),
+};
+
 const checkIssueSlopShape = {
   title: z.string().max(500).optional(),
   body: z.string().max(40000).optional(),
@@ -1079,6 +1115,12 @@ const STDIO_TOOL_DESCRIPTORS = [
     category: "review",
     description: "Assess the deterministic slop risk of a planned change from local diff metadata (paths + line counts) + the PR description — an agent-native, source-free quality self-check. Returns slopRisk (0-100), band, findings, and the rubric. Computed in-process; no repo data and no API round-trip.",
   },
+  {
+    name: "loopover_check_improvement_potential",
+    category: "review",
+    description:
+      "Assess the deterministic structural-improvement potential of a planned change from local diff metadata plus optional complexity/duplication/patch-coverage deltas — mirrors loopover_check_slop_risk on the positive axis. Same as `loopover-mcp improvement-potential` / POST /v1/lint/improvement-potential.",
+  },
   {
     name: "loopover_simulate_open_pr_pressure",
     category: "discovery",
@@ -1857,6 +1899,18 @@ registerStdioTool(
   (input: any) => toolResult("LoopOver slop-risk self-check.", { ...buildSlopAssessment(input), rubric: SLOP_RUBRIC_MARKDOWN }),
 );
 
+// #7759: CLI already proxies POST /v1/lint/improvement-potential (#6748); register the matching stdio tool.
+// Proxies rather than computing in-process (same rationale as the CLI): builders live app-side, not in
+// @loopover/engine. Forward the validated input object as the POST body — no local branching.
+registerStdioTool(
+  "loopover_check_improvement_potential",
+  {
+    description: stdioToolDescription("loopover_check_improvement_potential"),
+    inputSchema: checkImprovementPotentialShape,
+  },
+  async (input: any) => toolResult("LoopOver improvement-potential self-check.", await apiPost("/v1/lint/improvement-potential", input)),
+);
+
 // #6751: CLI mirror of the remote server's loopover_simulate_open_pr_pressure. Proxies rather than computing
 // in-process (like the boundary-tests mirror, #6750): simulateOpenPrPressure lives app-side in
 // src/services/open-pr-pressure-scenarios.ts, not in @loopover/engine, so POST /v1/lint/open-pr-pressure stays

test/unit/mcp-cli-improvement-potential-stdio.test.ts

@@ -0,0 +1,84 @@
+import { Client } from "@modelcontextprotocol/sdk/client/index.js";
+import { InMemoryTransport } from "@modelcontextprotocol/sdk/inMemory.js";
+import { mkdtempSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { afterAll, beforeAll, describe, expect, it } from "vitest";
+import { closeFixtureServer, startFixtureServer } from "./support/mcp-cli-harness";
+
+// #7759: in-process coverage for the loopover_check_improvement_potential stdio tool.
+// Same #7764 entrypoint-guard pattern as sibling maintainer tools — import .ts, hold exported `server`,
+// connect InMemoryTransport so v8/Codecov attributes registerStdioTool.
+const MODULES = ["../../packages/loopover-mcp/bin/loopover-mcp.ts"] as const;
+
+type BinModule = {
+  server: { connect: (transport: unknown) => Promise<void> };
+};
+
+let tempDir = "";
+const capturedRequests: Array<{ url: string; method: string }> = [];
+const loaded = new Map<string, BinModule>();
+
+beforeAll(async () => {
+  tempDir = mkdtempSync(join(tmpdir(), "loopover-improvement-potential-stdio-"));
+  const apiUrl = await startFixtureServer({
+    onApiRequest: (request) => {
+      if (request.url && request.url.includes("/lint/improvement-potential")) {
+        capturedRequests.push({ url: request.url ?? "", method: request.method ?? "GET" });
+      }
+    },
+  });
+  process.env.LOOPOVER_API_URL = apiUrl;
+  process.env.LOOPOVER_API_TOKEN = "in-process-token";
+  process.env.LOOPOVER_API_TIMEOUT_MS = "2000";
+  process.env.LOOPOVER_CONFIG_DIR = tempDir;
+  process.env.LOOPOVER_SKIP_NPM_VERSION_CHECK = "1";
+  for (const specifier of MODULES) {
+    loaded.set(specifier, (await import(specifier)) as unknown as BinModule);
+  }
+}, 120_000);
+
+afterAll(async () => {
+  await closeFixtureServer();
+  if (tempDir) rmSync(tempDir, { recursive: true, force: true });
+  delete process.env.LOOPOVER_API_URL;
+  delete process.env.LOOPOVER_API_TOKEN;
+  delete process.env.LOOPOVER_CONFIG_DIR;
+  delete process.env.LOOPOVER_SKIP_NPM_VERSION_CHECK;
+});
+
+describe("bin loopover_check_improvement_potential stdio tool (in-process, #7759)", () => {
+  it.each(MODULES)("registers and proxies POST /v1/lint/improvement-potential - %s", async (specifier) => {
+    capturedRequests.length = 0;
+    const mod = loaded.get(specifier)!;
+    const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+    await mod.server.connect(serverTransport);
+    const client = new Client({ name: "improvement-potential-stdio-test", version: "0.1.0" }, { capabilities: {} });
+    await client.connect(clientTransport);
+    try {
+      const { tools } = await client.listTools();
+      const tool = tools.find((entry) => entry.name === "loopover_check_improvement_potential");
+      expect(tool).toBeDefined();
+      expect(tool?.description).toMatch(/improvement/i);
+
+      const result = await client.callTool({
+        name: "loopover_check_improvement_potential",
+        arguments: {
+          changedFiles: [{ path: "src/widget.ts", additions: 80, deletions: 2 }],
+          testFiles: ["test/unit/widget.test.ts"],
+        },
+      });
+      expect(capturedRequests.length).toBe(1);
+      const captured = capturedRequests[0]!;
+      expect(captured.url).toContain("/v1/lint/improvement-potential");
+      expect(captured.method).toBe("POST");
+      expect(result.isError).toBeFalsy();
+      const text = JSON.stringify(result);
+      expect(text).toContain("improvementScore");
+      expect(text).toContain("minor");
+      expect(text).not.toMatch(/wallet|hotkey|reward|trust score/i);
+    } finally {
+      await client.close().catch(() => undefined);
+    }
+  });
+});

test/unit/mcp-tool-rename-aliases.test.ts

@@ -34,6 +34,7 @@
 // (#7762 registered the loopover_mark_notifications_read stdio tool, taking the count from 89 to 90.)
 // (#7760 registered the loopover_get_contributor_profile stdio tool, taking the count from 90 to 91.)
 // (#7763 registered the loopover_watch_issues stdio tool, taking the count from 91 to 92.)
+// (#7759 registered the loopover_check_improvement_potential stdio tool, taking the count from 92 to 93.)
 import { Client } from "@modelcontextprotocol/sdk/client/index.js";
 import { StdioClientTransport } from "@modelcontextprotocol/sdk/client/stdio.js";
 import { mkdtempSync, rmSync } from "node:fs";
@@ -80,14 +81,14 @@ describe("MCP legacy alias retirement (#4777) — discovery invariants", () => {
   });
   afterEach(disconnect);
 
-  it("lists exactly 92 loopover_ tools and zero gittensory_-prefixed aliases", async () => {
+  it("lists exactly 93 loopover_ tools and zero gittensory_-prefixed aliases", async () => {
     const { tools } = await client.listTools();
     const names = tools.map((t) => t.name);
     const primary = names.filter((n) => n.startsWith("loopover_"));
     const legacy = names.filter((n) => n.startsWith("gittensory_"));
-    expect(primary.length).toBe(92);
+    expect(primary.length).toBe(93);
     expect(legacy.length).toBe(0);
-    expect(names.length).toBe(92);
+    expect(names.length).toBe(93);
   });
 
   it("no loopover_ tool's description carries a stale deprecation notice", async () => {
@@ -99,14 +100,14 @@ describe("MCP legacy alias retirement (#4777) — discovery invariants", () => {
     }
   });
 
-  it("`loopover-mcp tools --json` reports the same 92-tool count the live server registers", async () => {
+  it("`loopover-mcp tools --json` reports the same 93-tool count the live server registers", async () => {
     const { tools } = await client.listTools();
     const payload = JSON.parse(run(["tools", "--json"])) as {
       count: number;
       tools: Array<{ name: string }>;
     };
     expect(payload.count).toBe(tools.length);
-    expect(payload.count).toBe(92);
+    expect(payload.count).toBe(93);
     expect([...payload.tools.map((t) => t.name)].sort()).toEqual(
       [...tools.map((t) => t.name)].sort(),
     );