diff --git a/src/mcp/server.ts b/src/mcp/server.ts
index 0fc7235fed..4bffeb4a19 100644
--- a/src/mcp/server.ts
+++ b/src/mcp/server.ts
@@ -87,6 +87,7 @@ import {
 } from "../signals/engine";
 import { buildContributorOpenPrMonitor } from "../signals/contributor-open-pr-monitor";
 import { buildLocalBranchAnalysis, findCurrentBranchPullRequest } from "../signals/local-branch";
+import { computeLocalScorerTokens } from "../signals/local-scorer";
 import { loadRepoFocusManifest } from "../signals/focus-manifest-loader";
 import { buildPredictedGateVerdict } from "../rules/predicted-gate";
 import { buildIssueSlopAssessment, buildSlopAssessment, ISSUE_SLOP_RUBRIC_MARKDOWN, SLOP_RUBRIC_MARKDOWN } from "../signals/slop";
@@ -181,6 +182,51 @@ const branchEligibilityShape = {
   stale: z.boolean().optional(),
 };
 
+// Changed-file metadata + local validation results — shared by the local-branch analysis and the #782 local
+// scorer. METADATA ONLY (paths + line counts), never source content, so the no-upload boundary holds.
+const changedFileSchema = z
+  .object({
+    path: z.string().min(1),
+    previousPath: z.string().min(1).optional(),
+    additions: z.number().int().min(0).optional(),
+    deletions: z.number().int().min(0).optional(),
+    status: z.enum(["added", "modified", "deleted", "renamed", "copied", "unknown"]).optional(),
+    binary: z.boolean().optional(),
+  })
+  .strict();
+
+const validationEntrySchema = z
+  .object({
+    command: z.string().min(1),
+    status: z.enum(["passed", "failed", "not_run", "skipped", "focused", "unknown"]),
+    summary: z.string().optional(),
+    durationMs: z.number().int().min(0).optional(),
+    exitCode: z.number().int().min(0).optional(),
+  })
+  .strict();
+
+// #782 run_local_scorer input — changed-file metadata + the local validation results.
+const runLocalScorerShape = {
+  changedFiles: z.array(changedFileSchema).min(1).max(500),
+  validation: z.array(validationEntrySchema).max(50).optional(),
+};
+
+const runLocalScorerOutputSchema = {
+  tokenScores: z
+    .object({
+      mode: z.string(),
+      activeModel: z.string().optional(),
+      sourceTokenScore: z.number().optional(),
+      totalTokenScore: z.number().optional(),
+      sourceLines: z.number().optional(),
+      testTokenScore: z.number().optional(),
+      nonCodeTokenScore: z.number().optional(),
+      warnings: z.array(z.string()).optional(),
+    })
+    .optional(),
+  usage: z.string().optional(),
+};
+
 const localBranchAnalysisShape = {
   login: z.string().min(1).max(SCENARIO_MAX_BRANCH_REF_CHARS),
   repoFullName: z.string().min(3).max(SCENARIO_MAX_REPO_FULL_NAME_CHARS),
@@ -192,35 +238,8 @@ const localBranchAnalysisShape = {
   mergeBaseSha: z.string().min(1).optional(),
   remoteTrackingSha: z.string().min(1).optional(),
   commitMessages: z.array(z.string()).max(30).optional(),
-  changedFiles: z
-    .array(
-      z
-        .object({
-          path: z.string().min(1),
-          previousPath: z.string().min(1).optional(),
-          additions: z.number().int().min(0).optional(),
-          deletions: z.number().int().min(0).optional(),
-          status: z.enum(["added", "modified", "deleted", "renamed", "copied", "unknown"]).optional(),
-          binary: z.boolean().optional(),
-        })
-        .strict(),
-    )
-    .max(500)
-    .optional(),
-  validation: z
-    .array(
-      z
-        .object({
-          command: z.string().min(1),
-          status: z.enum(["passed", "failed", "not_run", "skipped", "focused", "unknown"]),
-          summary: z.string().optional(),
-          durationMs: z.number().int().min(0).optional(),
-          exitCode: z.number().int().min(0).optional(),
-        })
-        .strict(),
-    )
-    .max(50)
-    .optional(),
+  changedFiles: z.array(changedFileSchema).max(500).optional(),
+  validation: z.array(validationEntrySchema).max(50).optional(),
   linkedIssues: z.array(z.number().int().positive()).max(SCENARIO_MAX_LINKED_ISSUE_NUMBERS).optional(),
   labels: z.array(z.string()).optional(),
   title: z.string().min(1).optional(),
@@ -996,6 +1015,17 @@ export class GittensoryMcp {
       async (input) => this.toolResult(await this.previewScore(input)),
     );
 
+    server.registerTool(
+      "gittensory_run_local_scorer",
+      {
+        description:
+          "Run Gittensory's deterministic local token scorer over changed-file metadata + local validation results (no source content). Returns token scores to pass back as the `localScorer` field of the score-preview / analyze tools (external_command mode), so the miner never runs the gittensor-root scorer by hand.",
+        inputSchema: runLocalScorerShape,
+        outputSchema: runLocalScorerOutputSchema,
+      },
+      async (input) => this.toolResult(this.runLocalScorer(input)),
+    );
+
     server.registerTool(
       "gittensory_explain_score_breakdown",
       {
@@ -1738,6 +1768,19 @@ export class GittensoryMcp {
     };
   }
 
+  // #782 — pure deterministic token scorer over caller-supplied changed-file metadata. No repo/contributor
+  // access required: it reveals nothing beyond a computation on the caller's own diff stats.
+  private runLocalScorer(input: z.infer<z.ZodObject<typeof runLocalScorerShape>>): ToolPayload {
+    const tokenScores = computeLocalScorerTokens({ changedFiles: input.changedFiles, validation: input.validation });
+    return {
+      summary: `Local token scores — ${tokenScores.sourceTokenScore} source / ${tokenScores.testTokenScore} test / ${tokenScores.nonCodeTokenScore} non-code (total ${tokenScores.totalTokenScore}).`,
+      data: {
+        tokenScores: tokenScores as unknown as Record<string, unknown>,
+        usage: "Pass `tokenScores` as the `localScorer` field of gittensory_preview_local_pr_score or the analyze tools to score this branch in external_command mode (off metadata-only).",
+      },
+    };
+  }
+
   private async explainScoreBreakdown(input: z.infer<z.ZodObject<typeof scorePreviewShape>>): Promise<ToolPayload> {
     if (!input.contributorLogin) throw new Error("contributorLogin is required for score breakdown.");
     this.requireContributorAccess(input.contributorLogin);
diff --git a/src/signals/local-scorer.ts b/src/signals/local-scorer.ts
new file mode 100644
index 0000000000..ef4d706b70
--- /dev/null
+++ b/src/signals/local-scorer.ts
@@ -0,0 +1,34 @@
+import { isCodeFile, isTestFile, type LocalBranchChangedFile, type LocalBranchScorer, type LocalBranchValidation } from "./local-branch";
+
+// #782 deterministic local scorer. Replicates the gittensor-root token-scoring view from changed-file METADATA
+// (paths + line counts) — never source content, so the no-upload boundary holds and it runs in every surface
+// (stdio package AND hosted Worker). It mirrors buildScorePreview's source/test/non-code classification, so
+// feeding its output back in as `localScorer` (mode external_command) flips the preview off metadata-only with
+// numbers it would otherwise have derived itself — closing the "miner runs the scorer manually" gap.
+
+const fileLines = (file: LocalBranchChangedFile): number => Math.max(0, file.additions ?? 0) + Math.max(0, file.deletions ?? 0);
+
+/**
+ * Compute token scores from changed-file metadata + the local validation results. `isCodeFile` already excludes
+ * tests, so source / test / non-code are disjoint. Binary files carry no token value and are dropped. A failed
+ * validation does not change the scores (they describe the diff) but is surfaced as a warning. Pure.
+ */
+export function computeLocalScorerTokens(input: { changedFiles: LocalBranchChangedFile[]; validation?: LocalBranchValidation[] | undefined }): LocalBranchScorer {
+  const files = input.changedFiles.filter((file) => !file.binary);
+  const testTokenScore = files.filter((file) => isTestFile(file.path)).reduce((sum, file) => sum + fileLines(file), 0);
+  const sourceTokenScore = files.filter((file) => isCodeFile(file.path)).reduce((sum, file) => sum + fileLines(file), 0);
+  const totalTokenScore = files.reduce((sum, file) => sum + fileLines(file), 0);
+  const nonCodeTokenScore = Math.max(0, totalTokenScore - sourceTokenScore - testTokenScore);
+  const failed = (input.validation ?? []).some((entry) => entry.status === "failed");
+  const warnings = failed ? ["Local validation reported failures — token scores describe the diff, not a passing build."] : [];
+  return {
+    mode: "external_command",
+    activeModel: "gittensory-deterministic",
+    sourceTokenScore,
+    totalTokenScore,
+    sourceLines: Math.max(1, sourceTokenScore || totalTokenScore || 1),
+    testTokenScore,
+    nonCodeTokenScore,
+    ...(warnings.length > 0 ? { warnings } : {}),
+  };
+}
diff --git a/test/unit/local-scorer.test.ts b/test/unit/local-scorer.test.ts
new file mode 100644
index 0000000000..2ee2f60700
--- /dev/null
+++ b/test/unit/local-scorer.test.ts
@@ -0,0 +1,60 @@
+import { describe, expect, it } from "vitest";
+import { computeLocalScorerTokens } from "../../src/signals/local-scorer";
+
+describe("computeLocalScorerTokens (#782)", () => {
+  it("classifies source / test / non-code from metadata and sums additions + deletions", () => {
+    const scorer = computeLocalScorerTokens({
+      changedFiles: [
+        { path: "src/foo.ts", additions: 10, deletions: 2 },
+        { path: "src/foo.test.ts", additions: 8, deletions: 0 },
+        { path: "README.md", additions: 5, deletions: 1 },
+      ],
+    });
+    expect(scorer).toMatchObject({
+      mode: "external_command",
+      activeModel: "gittensory-deterministic",
+      sourceTokenScore: 12,
+      testTokenScore: 8,
+      nonCodeTokenScore: 6,
+      totalTokenScore: 26,
+      sourceLines: 12,
+    });
+    expect(scorer.warnings).toBeUndefined();
+  });
+
+  it("drops binary files; with no source, sourceLines falls back to total (matching buildScorePreview)", () => {
+    const scorer = computeLocalScorerTokens({
+      changedFiles: [
+        { path: "img.png", additions: 100, binary: true },
+        { path: "docs.md", additions: 3 },
+      ],
+    });
+    expect(scorer.totalTokenScore).toBe(3); // the binary file carries no token value
+    expect(scorer.sourceTokenScore).toBe(0);
+    expect(scorer.nonCodeTokenScore).toBe(3);
+    expect(scorer.sourceLines).toBe(3); // no source → falls back to total, floored at 1
+  });
+
+  it("floors sourceLines at 1 for a diff with no line counts at all", () => {
+    const scorer = computeLocalScorerTokens({ changedFiles: [{ path: "docs.md" }] }); // additions/deletions omitted
+    expect(scorer.totalTokenScore).toBe(0);
+    expect(scorer.sourceLines).toBe(1);
+  });
+
+  it("surfaces a warning when local validation reports failures, without changing the scores", () => {
+    const scorer = computeLocalScorerTokens({
+      changedFiles: [{ path: "src/a.ts", additions: 4 }],
+      validation: [
+        { command: "npm test", status: "passed" },
+        { command: "npm run typecheck", status: "failed" },
+      ],
+    });
+    expect(scorer.sourceTokenScore).toBe(4);
+    expect(scorer.warnings?.[0]).toMatch(/validation reported failures/i);
+  });
+
+  it("emits no warning when validation passed or was not supplied", () => {
+    expect(computeLocalScorerTokens({ changedFiles: [{ path: "src/a.ts", additions: 1 }], validation: [{ command: "t", status: "passed" }] }).warnings).toBeUndefined();
+    expect(computeLocalScorerTokens({ changedFiles: [{ path: "src/a.ts", additions: 1 }] }).warnings).toBeUndefined();
+  });
+});
diff --git a/test/unit/mcp-run-local-scorer.test.ts b/test/unit/mcp-run-local-scorer.test.ts
new file mode 100644
index 0000000000..b5d451b95d
--- /dev/null
+++ b/test/unit/mcp-run-local-scorer.test.ts
@@ -0,0 +1,45 @@
+import { Client } from "@modelcontextprotocol/sdk/client/index.js";
+import { InMemoryTransport } from "@modelcontextprotocol/sdk/inMemory.js";
+import { describe, expect, it } from "vitest";
+import { GittensoryMcp } from "../../src/mcp/server";
+import { createTestEnv } from "../helpers/d1";
+
+async function connect() {
+  const server = new GittensoryMcp(createTestEnv()).createServer();
+  const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+  await server.connect(serverTransport);
+  const client = new Client({ name: "gittensory-scorer-test", version: "0.1.0" }, { capabilities: {} });
+  await client.connect(clientTransport);
+  return client;
+}
+
+describe("MCP gittensory_run_local_scorer (#782)", () => {
+  it("returns deterministic token scores from changed-file metadata (no repo/auth needed)", async () => {
+    const client = await connect();
+    const result = await client.callTool({
+      name: "gittensory_run_local_scorer",
+      arguments: {
+        changedFiles: [
+          { path: "src/foo.ts", additions: 10, deletions: 2 },
+          { path: "src/foo.test.ts", additions: 8 },
+          { path: "README.md", additions: 5 },
+        ],
+      },
+    });
+    expect(result.isError).toBeFalsy();
+    const data = result.structuredContent as { tokenScores: { mode: string; sourceTokenScore: number; testTokenScore: number; nonCodeTokenScore: number; totalTokenScore: number }; usage: string };
+    expect(data.tokenScores).toMatchObject({ mode: "external_command", sourceTokenScore: 12, testTokenScore: 8, nonCodeTokenScore: 5, totalTokenScore: 25 });
+    expect(data.usage).toMatch(/localScorer/);
+    expect(JSON.stringify(data)).not.toMatch(/wallet|hotkey|reward|payout|trust score/i);
+  });
+
+  it("surfaces a validation-failure warning", async () => {
+    const client = await connect();
+    const result = await client.callTool({
+      name: "gittensory_run_local_scorer",
+      arguments: { changedFiles: [{ path: "src/a.ts", additions: 4 }], validation: [{ command: "npm test", status: "failed" }] },
+    });
+    const data = result.structuredContent as { tokenScores: { warnings?: string[] } };
+    expect(data.tokenScores.warnings?.[0]).toMatch(/validation reported failures/i);
+  });
+});