diff --git a/packages/server-test/__tests__/formatters.test.ts b/packages/server-test/__tests__/formatters.test.ts
index ed2e6781..aa9d220c 100644
--- a/packages/server-test/__tests__/formatters.test.ts
+++ b/packages/server-test/__tests__/formatters.test.ts
@@ -1,5 +1,12 @@
 import { describe, it, expect } from "vitest";
-import { formatTestRun, formatCoverage } from "../src/lib/formatters.js";
+import {
+  formatTestRun,
+  formatCoverage,
+  compactTestRunMap,
+  formatTestRunCompact,
+  compactCoverageMap,
+  formatCoverageCompact,
+} from "../src/lib/formatters.js";
 import type { TestRun, Coverage } from "../src/schemas/index.js";
 
 describe("formatTestRun", () => {
@@ -229,3 +236,206 @@ describe("formatCoverage", () => {
     expect(output.split("\n")).toHaveLength(2);
   });
 });
+
+describe("compactTestRunMap", () => {
+  it("keeps summary, framework, and failure names only (drops messages, stacks, locations)", () => {
+    const run: TestRun = {
+      framework: "jest",
+      summary: { total: 10, passed: 7, failed: 3, skipped: 0, duration: 2.1 },
+      failures: [
+        {
+          name: "should validate email",
+          file: "api.test.ts",
+          line: 15,
+          message: "Expected valid@email.com to be valid",
+          stack: "Error: Expected valid@email.com...\n    at Object.<anonymous> (api.test.ts:15)",
+          expected: "true",
+          actual: "false",
+        },
+        {
+          name: "should parse config",
+          file: "utils.test.ts",
+          message: "Received null instead of config object",
+        },
+        {
+          name: "should handle timeout",
+          message: "Timeout after 5000ms",
+        },
+      ],
+    };
+
+    const compact = compactTestRunMap(run);
+
+    expect(compact.framework).toBe("jest");
+    expect(compact.summary).toEqual({
+      total: 10,
+      passed: 7,
+      failed: 3,
+      skipped: 0,
+      duration: 2.1,
+    });
+    expect(compact.failures).toEqual([
+      { name: "should validate email" },
+      { name: "should parse config" },
+      { name: "should handle timeout" },
+    ]);
+    // Verify verbose fields are stripped from each failure
+    expect(compact.failures[0]).not.toHaveProperty("message");
+    expect(compact.failures[0]).not.toHaveProperty("file");
+    expect(compact.failures[0]).not.toHaveProperty("line");
+    expect(compact.failures[0]).not.toHaveProperty("stack");
+    expect(compact.failures[0]).not.toHaveProperty("expected");
+    expect(compact.failures[0]).not.toHaveProperty("actual");
+  });
+
+  it("returns empty failures for passing run", () => {
+    const run: TestRun = {
+      framework: "vitest",
+      summary: { total: 5, passed: 5, failed: 0, skipped: 0, duration: 0.3 },
+      failures: [],
+    };
+
+    const compact = compactTestRunMap(run);
+
+    expect(compact.failures).toEqual([]);
+    expect(compact.summary.failed).toBe(0);
+  });
+});
+
+describe("formatTestRunCompact", () => {
+  it("formats compact test run with failure names only", () => {
+    const compact = {
+      framework: "jest",
+      summary: { total: 10, passed: 7, failed: 3, skipped: 0, duration: 2.1 },
+      failures: [
+        { name: "should validate email" },
+        { name: "should parse config" },
+        { name: "should handle timeout" },
+      ],
+    };
+
+    const output = formatTestRunCompact(compact);
+
+    expect(output).toContain("FAIL");
+    expect(output).toContain("(jest)");
+    expect(output).toContain("10 tests");
+    expect(output).toContain("3 failed");
+    expect(output).toContain("FAIL should validate email");
+    expect(output).toContain("FAIL should parse config");
+    expect(output).toContain("FAIL should handle timeout");
+    // Should NOT contain verbose failure details
+    expect(output).not.toContain("Expected");
+    expect(output).not.toContain("Received");
+    expect(output).not.toContain("api.test.ts");
+  });
+
+  it("formats compact passing run as PASS with no failure lines", () => {
+    const compact = {
+      framework: "vitest",
+      summary: { total: 5, passed: 5, failed: 0, skipped: 0, duration: 0.3 },
+      failures: [] as Array<{ name: string }>,
+    };
+
+    const output = formatTestRunCompact(compact);
+
+    expect(output).toContain("PASS");
+    expect(output.split("\n")).toHaveLength(1);
+  });
+});
+
+describe("compactCoverageMap", () => {
+  it("keeps summary and totalFiles, drops per-file details", () => {
+    const cov: Coverage = {
+      framework: "jest",
+      summary: { lines: 87.5, branches: 66.67, functions: 100 },
+      files: [
+        { file: "src/auth.ts", lines: 92, branches: 80, functions: 100 },
+        { file: "src/api.ts", lines: 80, branches: 50, functions: 100 },
+        { file: "src/utils.ts", lines: 95, branches: 70, functions: 100 },
+      ],
+    };
+
+    const compact = compactCoverageMap(cov);
+
+    expect(compact.framework).toBe("jest");
+    expect(compact.summary).toEqual({ lines: 87.5, branches: 66.67, functions: 100 });
+    expect(compact.totalFiles).toBe(3);
+    // Verify per-file details are not present
+    expect(compact).not.toHaveProperty("files");
+  });
+
+  it("returns totalFiles 0 for empty files array", () => {
+    const cov: Coverage = {
+      framework: "pytest",
+      summary: { lines: 0 },
+      files: [],
+    };
+
+    const compact = compactCoverageMap(cov);
+
+    expect(compact.totalFiles).toBe(0);
+  });
+
+  it("preserves optional summary fields when present", () => {
+    const cov: Coverage = {
+      framework: "mocha",
+      summary: { lines: 50 },
+      files: [{ file: "app.js", lines: 50 }],
+    };
+
+    const compact = compactCoverageMap(cov);
+
+    expect(compact.summary.lines).toBe(50);
+    expect(compact.summary.branches).toBeUndefined();
+    expect(compact.summary.functions).toBeUndefined();
+    expect(compact.totalFiles).toBe(1);
+  });
+});
+
+describe("formatCoverageCompact", () => {
+  it("formats compact coverage with summary and file count", () => {
+    const compact = {
+      framework: "jest",
+      summary: { lines: 87.5, branches: 66.67, functions: 100 },
+      totalFiles: 3,
+    };
+
+    const output = formatCoverageCompact(compact);
+
+    expect(output).toContain("Coverage (jest)");
+    expect(output).toContain("87.5% lines");
+    expect(output).toContain("66.67% branches");
+    expect(output).toContain("100% functions");
+    expect(output).toContain("3 file(s) analyzed");
+    // Should NOT contain per-file details
+    expect(output).not.toContain("src/auth.ts");
+  });
+
+  it("formats compact coverage without optional branches/functions", () => {
+    const compact = {
+      framework: "pytest",
+      summary: { lines: 75 },
+      totalFiles: 5,
+    };
+
+    const output = formatCoverageCompact(compact);
+
+    expect(output).toContain("75% lines");
+    expect(output).toContain("5 file(s) analyzed");
+    expect(output).not.toContain("branches");
+    expect(output).not.toContain("functions");
+  });
+
+  it("formats compact coverage with zero files", () => {
+    const compact = {
+      framework: "mocha",
+      summary: { lines: 0, branches: 0, functions: 0 },
+      totalFiles: 0,
+    };
+
+    const output = formatCoverageCompact(compact);
+
+    expect(output).toContain("0% lines");
+    expect(output).toContain("0 file(s) analyzed");
+  });
+});
diff --git a/packages/server-test/src/lib/formatters.ts b/packages/server-test/src/lib/formatters.ts
index 2fb5ebf6..c453859c 100644
--- a/packages/server-test/src/lib/formatters.ts
+++ b/packages/server-test/src/lib/formatters.ts
@@ -22,9 +22,77 @@ export function formatCoverage(c: Coverage): string {
   if (c.summary.branches !== undefined) parts[0] += `, ${c.summary.branches}% branches`;
   if (c.summary.functions !== undefined) parts[0] += `, ${c.summary.functions}% functions`;
 
-  for (const f of c.files) {
+  for (const f of c.files ?? []) {
     parts.push(`  ${f.file}: ${f.lines}% lines`);
   }
 
   return parts.join("\n");
 }
+
+// ── Compact types, mappers, and formatters ───────────────────────────
+
+/** Compact test run: summary + framework + failure names only (no messages, stacks, expected/actual). */
+export interface TestRunCompact {
+  [key: string]: unknown;
+  framework: string;
+  summary: {
+    total: number;
+    passed: number;
+    failed: number;
+    skipped: number;
+    duration: number;
+  };
+  failures: Array<{ name: string }>;
+}
+
+export function compactTestRunMap(r: TestRun): TestRunCompact {
+  return {
+    framework: r.framework,
+    summary: { ...r.summary },
+    failures: r.failures.map((f) => ({ name: f.name })),
+  };
+}
+
+export function formatTestRunCompact(r: TestRunCompact): string {
+  const status = r.summary.failed > 0 ? "FAIL" : "PASS";
+  const parts = [
+    `${status} (${r.framework}) ${r.summary.total} tests: ${r.summary.passed} passed, ${r.summary.failed} failed, ${r.summary.skipped} skipped [${r.summary.duration}s]`,
+  ];
+
+  for (const f of r.failures) {
+    parts.push(`  FAIL ${f.name}`);
+  }
+
+  return parts.join("\n");
+}
+
+/** Compact coverage: summary totals + file count only (no per-file details). */
+export interface CoverageCompact {
+  [key: string]: unknown;
+  framework: string;
+  summary: {
+    lines: number;
+    branches?: number;
+    functions?: number;
+  };
+  totalFiles: number;
+}
+
+export function compactCoverageMap(c: Coverage): CoverageCompact {
+  return {
+    framework: c.framework,
+    summary: { ...c.summary },
+    totalFiles: (c.files ?? []).length,
+  };
+}
+
+export function formatCoverageCompact(c: CoverageCompact): string {
+  const parts = [`Coverage (${c.framework}): ${c.summary.lines}% lines`];
+
+  if (c.summary.branches !== undefined) parts[0] += `, ${c.summary.branches}% branches`;
+  if (c.summary.functions !== undefined) parts[0] += `, ${c.summary.functions}% functions`;
+
+  parts.push(`${c.totalFiles} file(s) analyzed`);
+
+  return parts.join("\n");
+}
diff --git a/packages/server-test/src/schemas/index.ts b/packages/server-test/src/schemas/index.ts
index a869d17c..bbed225a 100644
--- a/packages/server-test/src/schemas/index.ts
+++ b/packages/server-test/src/schemas/index.ts
@@ -5,7 +5,7 @@ export const TestFailureSchema = z.object({
   name: z.string(),
   file: z.string().optional(),
   line: z.number().optional(),
-  message: z.string(),
+  message: z.string().optional(),
   expected: z.string().optional(),
   actual: z.string().optional(),
   stack: z.string().optional(),
@@ -45,7 +45,8 @@ export const CoverageSchema = z.object({
     branches: z.number().optional(),
     functions: z.number().optional(),
   }),
-  files: z.array(CoverageFileSchema),
+  files: z.array(CoverageFileSchema).optional(),
+  totalFiles: z.number().optional(),
 });
 
 export type Coverage = z.infer<typeof CoverageSchema>;
diff --git a/packages/server-test/src/tools/coverage.ts b/packages/server-test/src/tools/coverage.ts
index 788fe883..08dd2194 100644
--- a/packages/server-test/src/tools/coverage.ts
+++ b/packages/server-test/src/tools/coverage.ts
@@ -1,12 +1,12 @@
 import { z } from "zod";
 import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { dualOutput, run, INPUT_LIMITS } from "@paretools/shared";
+import { compactDualOutput, run, INPUT_LIMITS } from "@paretools/shared";
 import { detectFramework, type Framework } from "../lib/detect.js";
 import { parsePytestCoverage } from "../lib/parsers/pytest.js";
 import { parseJestCoverage } from "../lib/parsers/jest.js";
 import { parseVitestCoverage } from "../lib/parsers/vitest.js";
 import { parseMochaCoverage } from "../lib/parsers/mocha.js";
-import { formatCoverage } from "../lib/formatters.js";
+import { formatCoverage, compactCoverageMap, formatCoverageCompact } from "../lib/formatters.js";
 import { CoverageSchema } from "../schemas/index.js";
 
 function getCoverageCommand(framework: Framework): { cmd: string; cmdArgs: string[] } {
@@ -42,10 +42,17 @@ export function registerCoverageTool(server: McpServer) {
           .enum(["pytest", "jest", "vitest", "mocha"])
           .optional()
           .describe("Force a specific framework instead of auto-detecting"),
+        compact: z
+          .boolean()
+          .optional()
+          .default(true)
+          .describe(
+            "Auto-compact when structured output exceeds raw CLI tokens. Set false to always get full schema.",
+          ),
       },
       outputSchema: CoverageSchema,
     },
-    async ({ path, framework }) => {
+    async ({ path, framework, compact }) => {
       const cwd = path || process.cwd();
       const detected = framework || (await detectFramework(cwd));
       const { cmd, cmdArgs } = getCoverageCommand(detected);
@@ -69,7 +76,14 @@ export function registerCoverageTool(server: McpServer) {
           break;
       }
 
-      return dualOutput(coverage, formatCoverage);
+      return compactDualOutput(
+        coverage,
+        result.stdout,
+        formatCoverage,
+        compactCoverageMap,
+        formatCoverageCompact,
+        compact === false,
+      );
     },
   );
 }
diff --git a/packages/server-test/src/tools/run.ts b/packages/server-test/src/tools/run.ts
index 6ab4c7a9..18036103 100644
--- a/packages/server-test/src/tools/run.ts
+++ b/packages/server-test/src/tools/run.ts
@@ -4,13 +4,13 @@ import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { randomUUID } from "node:crypto";
 import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import { dualOutput, run, assertNoFlagInjection, INPUT_LIMITS } from "@paretools/shared";
+import { compactDualOutput, run, assertNoFlagInjection, INPUT_LIMITS } from "@paretools/shared";
 import { detectFramework, type Framework } from "../lib/detect.js";
 import { parsePytestOutput } from "../lib/parsers/pytest.js";
 import { parseJestJson } from "../lib/parsers/jest.js";
 import { parseVitestJson } from "../lib/parsers/vitest.js";
 import { parseMochaJson } from "../lib/parsers/mocha.js";
-import { formatTestRun } from "../lib/formatters.js";
+import { formatTestRun, compactTestRunMap, formatTestRunCompact } from "../lib/formatters.js";
 import { TestRunSchema } from "../schemas/index.js";
 
 function getRunCommand(framework: Framework, args: string[]): { cmd: string; cmdArgs: string[] } {
@@ -59,10 +59,17 @@ export function registerRunTool(server: McpServer) {
           .optional()
           .default([])
           .describe("Additional arguments to pass to the test runner"),
+        compact: z
+          .boolean()
+          .optional()
+          .default(true)
+          .describe(
+            "Auto-compact when structured output exceeds raw CLI tokens. Set false to always get full schema.",
+          ),
       },
       outputSchema: TestRunSchema,
     },
-    async ({ path, framework, filter, updateSnapshots, args }) => {
+    async ({ path, framework, filter, updateSnapshots, args, compact }) => {
       for (const a of args ?? []) {
         assertNoFlagInjection(a, "args");
       }
@@ -133,7 +140,14 @@ export function registerRunTool(server: McpServer) {
         }
       }
 
-      return dualOutput(testRun, formatTestRun);
+      return compactDualOutput(
+        testRun,
+        result.stdout,
+        formatTestRun,
+        compactTestRunMap,
+        formatTestRunCompact,
+        compact === false,
+      );
     },
   );
 }