diff --git a/extensions/anthropic/cli-backend.ts b/extensions/anthropic/cli-backend.ts
index 852736d78c43..4939b90b650c 100644
--- a/extensions/anthropic/cli-backend.ts
+++ b/extensions/anthropic/cli-backend.ts
@@ -11,6 +11,7 @@ import {
   CLI_FRESH_WATCHDOG_DEFAULTS,
   CLI_RESUME_WATCHDOG_DEFAULTS,
 } from "openclaw/plugin-sdk/cli-backend";
+import { parseClaudeCliJsonlEvent } from "./cli-output.js";
 import {
   CLAUDE_CLI_BACKEND_ID,
   CLAUDE_CLI_DEFAULT_MODEL_REF,
@@ -237,6 +238,7 @@ export function buildAnthropicCliBackend(): CliBackendPlugin {
           }
         : undefined;
     },
+    parseJsonlEvent: parseClaudeCliJsonlEvent,
     resolveExecutionArgs: resolveClaudeCliExecutionArgs,
   };
 }
diff --git a/extensions/anthropic/cli-output.test.ts b/extensions/anthropic/cli-output.test.ts
new file mode 100644
index 000000000000..cf9b19516506
--- /dev/null
+++ b/extensions/anthropic/cli-output.test.ts
@@ -0,0 +1,293 @@
+import { describe, expect, it } from "vitest";
+import { buildAnthropicCliBackend } from "./cli-backend.js";
+
+const MOCK_RAW_TOOL_OUTPUT = [
+  "I'll inspect the synthetic report.",
+  "",
+  '<invoke name="Bash">',
+  '<parameter name="command">wc -l /tmp/mock-report.md</parameter>',
+  '<parameter name="description">Verify the mock report</parameter>',
+  "</invoke>",
+  "",
+  "12 /tmp/mock-report.md",
+  "",
+  "The synthetic report has 12 lines.",
+].join("\n");
+
+function parseResult(result: string) {
+  return buildAnthropicCliBackend().parseJsonlEvent?.(
+    JSON.stringify({ type: "result", subtype: "success", result }),
+    {
+      backendId: "claude-cli",
+      backend: buildAnthropicCliBackend().config,
+    },
+  );
+}
+
+describe("Claude CLI output validation", () => {
+  it("rejects mocked raw tool protocol returned as terminal assistant text", () => {
+    expect(parseResult(MOCK_RAW_TOOL_OUTPUT)).toEqual({
+      kind: "result",
+      errorText: expect.stringContaining("raw tool protocol appeared as assistant text"),
+    });
+  });
+
+  it.each(["\\u003c", "\\u003C"])(
+    "rejects the %s-escaped JSON form reported by upstream Claude Code",
+    (escapedLessThan) => {
+      const line = JSON.stringify({ type: "result", result: MOCK_RAW_TOOL_OUTPUT }).replaceAll(
+        "<",
+        escapedLessThan,
+      );
+      const backend = buildAnthropicCliBackend();
+
+      expect(
+        backend.parseJsonlEvent?.(line, { backendId: backend.id, backend: backend.config }),
+      ).toEqual({
+        kind: "result",
+        errorText: expect.stringContaining("raw tool protocol appeared as assistant text"),
+      });
+    },
+  );
+
+  it("rejects standalone protocol with CRLF line endings", () => {
+    expect(parseResult(MOCK_RAW_TOOL_OUTPUT.replaceAll("\n", "\r\n"))).toEqual({
+      kind: "result",
+      errorText: expect.stringContaining("raw tool protocol appeared as assistant text"),
+    });
+  });
+
+  it("rejects a complete invocation whose parameter payload exceeds the opening-tag lookahead", () => {
+    expect(
+      parseResult(
+        [
+          "Writing the generated fixture.",
+          '<invoke name="Write">',
+          `<parameter name="content">${"x".repeat(3_000)}</parameter>`,
+          "</invoke>",
+        ].join("\n"),
+      ),
+    ).toEqual({
+      kind: "result",
+      errorText: expect.stringContaining("raw tool protocol appeared as assistant text"),
+    });
+  });
+
+  it.each(["call", "count", "court", "Bash"])(
+    "rejects the upstream-observed %s prefix when the protocol block is truncated",
+    (prefix) => {
+      expect(
+        parseResult(
+          [
+            "I will inspect it.",
+            prefix,
+            '<invoke name="Bash">',
+            '<parameter name="command">wc -l /tmp/mock-report.md',
+          ].join("\n"),
+        ),
+      ).toEqual({
+        kind: "result",
+        errorText: expect.stringContaining("raw tool protocol appeared as assistant text"),
+      });
+    },
+  );
+
+  it("does not let a later inline close token mask an observed truncated leak", () => {
+    expect(
+      parseResult(
+        [
+          "call",
+          '<invoke name="Bash">',
+          '<parameter name="command">pwd',
+          "Documentation may mention </invoke> inline.",
+        ].join("\n"),
+      ),
+    ).toEqual({
+      kind: "result",
+      errorText: expect.stringContaining("raw tool protocol appeared as assistant text"),
+    });
+  });
+
+  it("does not let inline close prose before the parameter mask an observed truncated leak", () => {
+    expect(
+      parseResult(
+        [
+          "call",
+          '<invoke name="Bash">',
+          "Documentation may mention </invoke> inline.",
+          '<parameter name="command">pwd',
+        ].join("\n"),
+      ),
+    ).toEqual({
+      kind: "result",
+      errorText: expect.stringContaining("raw tool protocol appeared as assistant text"),
+    });
+  });
+
+  it("continues to a valid parameter after a non-evidentiary parameter-like tag", () => {
+    expect(
+      parseResult(
+        [
+          '<invoke name="Bash">',
+          '<parameter data-name="example">ignored</parameter>',
+          '<parameter name="command">pwd</parameter>',
+          "</invoke>",
+        ].join("\n"),
+      ),
+    ).toEqual({
+      kind: "result",
+      errorText: expect.stringContaining("raw tool protocol appeared as assistant text"),
+    });
+  });
+
+  it("rejects a complete unfenced protocol example as the accepted false-positive tradeoff", () => {
+    expect(
+      parseResult(
+        [
+          "Here is the exact raw protocol for documentation:",
+          '<invoke name="Bash">',
+          '<parameter name="command">pwd</parameter>',
+          "</invoke>",
+        ].join("\n"),
+      ),
+    ).toEqual({
+      kind: "result",
+      errorText: expect.stringContaining("raw tool protocol appeared as assistant text"),
+    });
+  });
+
+  it.each([
+    ["ordinary chat", "The washer report is ready. Here are three recommendations."],
+    [
+      "inline protocol discussion",
+      'Claude printed `<invoke name="Bash"><parameter name="command">pwd</parameter></invoke>`.',
+    ],
+    [
+      "fenced protocol example",
+      [
+        "Example:",
+        "```xml",
+        '<invoke name="Bash">',
+        '<parameter name="command">pwd</parameter>',
+        "</invoke>",
+        "```",
+      ].join("\n"),
+    ],
+    [
+      "unterminated fenced protocol example",
+      [
+        "Example:",
+        "~~~xml",
+        '<invoke name="Bash">',
+        '<parameter name="command">pwd</parameter>',
+        "</invoke>",
+      ].join("\n"),
+    ],
+    [
+      "same-line XML prose",
+      'Use <invoke name="Bash"><parameter name="command">pwd</parameter></invoke> only as an example.',
+    ],
+    [
+      "line-leading protocol prose",
+      [
+        '<invoke name="Bash">...</invoke> denotes a call.',
+        '<parameter name="command">...</parameter> denotes its argument.',
+      ].join("\n"),
+    ],
+    [
+      "indented protocol example",
+      [
+        '    <invoke name="Bash">',
+        '    <parameter name="command">pwd</parameter>',
+        "    </invoke>",
+      ].join("\n"),
+    ],
+    [
+      "unrelated lowercase XML",
+      ['<invoke name="transform">', '<parameter name="input">text</parameter>', "</invoke>"].join(
+        "\n",
+      ),
+    ],
+    [
+      "similarly named XML elements",
+      [
+        '<invoke-example name="Bash">',
+        '<parameter-example name="command">pwd</parameter-example>',
+        "</invoke-example>",
+      ].join("\n"),
+    ],
+    [
+      "similarly named XML attributes",
+      [
+        '<invoke data-name="Bash">',
+        '<parameter data-name="command">pwd</parameter>',
+        "</invoke>",
+      ].join("\n"),
+    ],
+    [
+      "name text inside unrelated quoted attributes",
+      [
+        "<invoke description=\"tool name='Bash'\">",
+        "<parameter description=\"argument name='command'\">pwd</parameter>",
+        "</invoke>",
+      ].join("\n"),
+    ],
+    ["standalone invoke without parameters", '<invoke name="Bash">no parameter block</invoke>'],
+    [
+      "complete parameterless invocation not observed upstream",
+      ['<invoke name="mcp__server__get_current_time">', "</invoke>"].join("\n"),
+    ],
+    [
+      "parameter evidence belonging to a later lowercase invocation",
+      [
+        '<invoke name="Bash">',
+        "</invoke>",
+        '<invoke name="transform">',
+        '<parameter name="input">text</parameter>',
+        "</invoke>",
+      ].join("\n"),
+    ],
+    [
+      "later lowercase invocation after a truncated parameterless invocation",
+      [
+        "call",
+        '<invoke name="Bash">',
+        '<invoke name="transform">',
+        '<parameter name="input">text</parameter>',
+        "</invoke>",
+      ].join("\n"),
+    ],
+    [
+      "unprefixed truncated protocol example",
+      [
+        "Here is an incomplete protocol example:",
+        '<invoke name="Bash">',
+        '<parameter name="command">pwd',
+      ].join("\n"),
+    ],
+    [
+      "namespaced protocol example not observed upstream",
+      [
+        '<antml:invoke name="Bash">',
+        '<antml:parameter name="command">pwd</antml:parameter>',
+        "</antml:invoke>",
+      ].join("\n"),
+    ],
+    ["long ordinary report", `Summary\n\n${"Normal report text. ".repeat(20_000)}`],
+  ])("preserves %s", (_name, text) => {
+    expect(parseResult(text)).toBeNull();
+  });
+
+  it("ignores malformed and non-terminal JSONL frames", () => {
+    const backend = buildAnthropicCliBackend();
+    const context = { backendId: backend.id, backend: backend.config };
+
+    expect(backend.parseJsonlEvent?.("not json <invoke <parameter", context)).toBeNull();
+    expect(
+      backend.parseJsonlEvent?.(
+        JSON.stringify({ type: "assistant", result: MOCK_RAW_TOOL_OUTPUT }),
+        context,
+      ),
+    ).toBeNull();
+  });
+});
diff --git a/extensions/anthropic/cli-output.ts b/extensions/anthropic/cli-output.ts
new file mode 100644
index 000000000000..b1100a5b7cf3
--- /dev/null
+++ b/extensions/anthropic/cli-output.ts
@@ -0,0 +1,199 @@
+import type { CliBackendParseJsonlEvent } from "openclaw/plugin-sdk/cli-backend";
+import { isRecord } from "openclaw/plugin-sdk/string-coerce-runtime";
+import { findCodeRegions, type CodeRegion } from "openclaw/plugin-sdk/text-chunking";
+
+const CLAUDE_RAW_TOOL_OUTPUT_ERROR =
+  "Claude CLI returned malformed tool output (invalid request format): raw tool protocol appeared as assistant text. OpenClaw refused to persist or deliver it.";
+
+const RAW_INVOKE_TAG_RE = /<invoke(?=[ \t>])[^<>\r\n]*>/gu;
+const RAW_PARAMETER_TAG_RE = /<parameter(?=[ \t>])[^<>\r\n]*>/gu;
+const RAW_INVOKE_CLOSE_TAG_RE = /<\/invoke[ \t]*>/gu;
+const RAW_PARAMETER_LOOKAHEAD_CHARS = 2_048;
+const OBSERVED_TRUNCATED_LEAK_PREFIXES = new Set(["call", "count", "court"]);
+
+function readTagNameAttribute(tag: string, elementName: "invoke" | "parameter"): string {
+  const attribute = /[ \t]+([^\s=/>]+)[ \t]*=[ \t]*(?:"([^"]*)"|'([^']*)')/gy;
+  const tagEnd = tag.length - 1;
+  let cursor = elementName.length + 1;
+  while (cursor < tagEnd) {
+    attribute.lastIndex = cursor;
+    const match = attribute.exec(tag);
+    if (!match) {
+      return "";
+    }
+    if (match[1] === "name") {
+      return match[2] ?? match[3] ?? "";
+    }
+    cursor = attribute.lastIndex;
+  }
+  return "";
+}
+
+function isStandaloneLineTag(text: string, index: number): boolean {
+  const lineStart = text.lastIndexOf("\n", index - 1) + 1;
+  return /^[ ]{0,3}$/u.test(text.slice(lineStart, index));
+}
+
+function isStandaloneOpeningTagLine(text: string, index: number, tagLength: number): boolean {
+  if (!isStandaloneLineTag(text, index)) {
+    return false;
+  }
+  const lineEnd = text.indexOf("\n", index + tagLength);
+  const trailingText = text.slice(index + tagLength, lineEnd === -1 ? text.length : lineEnd);
+  return /^[ \t]*\r?$/u.test(trailingText);
+}
+
+function isInsideCodeRegion(index: number, regions: CodeRegion[]): boolean {
+  let low = 0;
+  let high = regions.length - 1;
+  while (low <= high) {
+    const middle = Math.floor((low + high) / 2);
+    const region = regions[middle];
+    if (!region) {
+      return false;
+    }
+    if (index < region.start) {
+      high = middle - 1;
+    } else if (index >= region.end) {
+      low = middle + 1;
+    } else {
+      return true;
+    }
+  }
+  return false;
+}
+
+function hasObservedTruncatedLeakPrefix(text: string, index: number, toolName: string): boolean {
+  const previousNonEmptyLine = text
+    .slice(0, index)
+    .split(/\r?\n/gu)
+    .findLast((line) => line.trim().length > 0)
+    ?.trim();
+  return (
+    previousNonEmptyLine === toolName ||
+    (previousNonEmptyLine !== undefined &&
+      OBSERVED_TRUNCATED_LEAK_PREFIXES.has(previousNonEmptyLine))
+  );
+}
+
+function findNextStandaloneTag(
+  text: string,
+  index: number,
+  regions: CodeRegion[],
+  pattern: RegExp,
+): number | null {
+  const scanner = new RegExp(pattern.source, pattern.flags);
+  scanner.lastIndex = index;
+  for (let match = scanner.exec(text); match; match = scanner.exec(text)) {
+    if (
+      isStandaloneOpeningTagLine(text, match.index, match[0].length) &&
+      !isInsideCodeRegion(match.index, regions)
+    ) {
+      return match.index;
+    }
+  }
+  return null;
+}
+
+/** Detect Claude's legacy tool protocol only when it occupies standalone assistant lines. */
+function hasClaudeRawToolInvocation(text: string): boolean {
+  if (!text.includes("<invoke") || !text.includes("<parameter")) {
+    return false;
+  }
+
+  const codeRegions = findCodeRegions(text);
+  RAW_INVOKE_TAG_RE.lastIndex = 0;
+  for (const match of text.matchAll(RAW_INVOKE_TAG_RE)) {
+    const index = match.index;
+    const toolName = readTagNameAttribute(match[0], "invoke");
+    if (
+      (!/^[A-Z]/u.test(toolName) && !toolName.startsWith("mcp__")) ||
+      !isStandaloneOpeningTagLine(text, index, match[0].length) ||
+      isInsideCodeRegion(index, codeRegions)
+    ) {
+      continue;
+    }
+
+    const invocationBodyStart = index + match[0].length;
+    const invokeCloseIndex = findNextStandaloneTag(
+      text,
+      invocationBodyStart,
+      codeRegions,
+      RAW_INVOKE_CLOSE_TAG_RE,
+    );
+    const nextInvokeIndex = findNextStandaloneTag(
+      text,
+      invocationBodyStart,
+      codeRegions,
+      RAW_INVOKE_TAG_RE,
+    );
+    const completeInvokeCloseIndex =
+      invokeCloseIndex !== null && (nextInvokeIndex === null || invokeCloseIndex < nextInvokeIndex)
+        ? invokeCloseIndex
+        : null;
+    const parameterSearchEnd = Math.min(
+      text.length,
+      invocationBodyStart + RAW_PARAMETER_LOOKAHEAD_CHARS,
+      completeInvokeCloseIndex ?? text.length,
+      nextInvokeIndex ?? text.length,
+    );
+    const parameterText = text.slice(invocationBodyStart, parameterSearchEnd);
+    let parameterIndex: number | null = null;
+    for (const parameterMatch of parameterText.matchAll(RAW_PARAMETER_TAG_RE)) {
+      const candidateIndex = invocationBodyStart + parameterMatch.index;
+      if (
+        readTagNameAttribute(parameterMatch[0], "parameter") &&
+        isStandaloneLineTag(text, candidateIndex) &&
+        !isInsideCodeRegion(candidateIndex, codeRegions)
+      ) {
+        parameterIndex = candidateIndex;
+        break;
+      }
+    }
+    if (parameterIndex === null) {
+      continue;
+    }
+    if (
+      // Upstream shows both complete blocks and prefix-led truncated blocks. Requiring a close
+      // misses the latter; requiring a prefix misses the complete leak reproduced in this PR.
+      // Complete unfenced examples remain the accepted false positive and surface as format errors.
+      completeInvokeCloseIndex !== null ||
+      (completeInvokeCloseIndex === null && hasObservedTruncatedLeakPrefix(text, index, toolName))
+    ) {
+      return true;
+    }
+  }
+  return false;
+}
+
+/** Reject malformed terminal Claude results before the generic CLI runner accepts them as prose. */
+export const parseClaudeCliJsonlEvent: CliBackendParseJsonlEvent = (line) => {
+  const mightContainRawToolProtocol =
+    (line.includes("<invoke") ||
+      line.includes("\\u003cinvoke") ||
+      line.includes("\\u003Cinvoke")) &&
+    (line.includes("<parameter") ||
+      line.includes("\\u003cparameter") ||
+      line.includes("\\u003Cparameter"));
+  if (!mightContainRawToolProtocol) {
+    return null;
+  }
+
+  let parsed: unknown;
+  try {
+    parsed = JSON.parse(line);
+  } catch {
+    return null;
+  }
+  if (
+    !isRecord(parsed) ||
+    parsed.type !== "result" ||
+    typeof parsed.result !== "string" ||
+    !hasClaudeRawToolInvocation(parsed.result)
+  ) {
+    return null;
+  }
+  // Core classifies this exact phrase as a format failure, enabling safe fallback instead of
+  // accepting the malformed terminal result as a successful assistant response.
+  return { kind: "result", errorText: CLAUDE_RAW_TOOL_OUTPUT_ERROR };
+};
diff --git a/src/agents/cli-output.test.ts b/src/agents/cli-output.test.ts
index e511869058e2..f1bcb040bc57 100644
--- a/src/agents/cli-output.test.ts
+++ b/src/agents/cli-output.test.ts
@@ -1211,6 +1211,29 @@ describe("parseCliJsonl", () => {
 });
 
 describe("parseCliOutput", () => {
+  it("applies a backend JSONL hook when reparsing complete output", () => {
+    const parseJsonlEvent = vi.fn(() => ({
+      kind: "result" as const,
+      errorText: "invalid request format: malformed backend result",
+    }));
+
+    expect(
+      parseCliOutput({
+        raw: JSON.stringify({ type: "result", result: "malformed" }),
+        backend: { command: "acme", output: "jsonl" },
+        providerId: "acme-cli",
+        parseJsonlEvent,
+        outputMode: "jsonl",
+      }),
+    ).toEqual({
+      text: "",
+      sessionId: undefined,
+      usage: undefined,
+      errorText: "invalid request format: malformed backend result",
+    });
+    expect(parseJsonlEvent).toHaveBeenCalledOnce();
+  });
+
   it.each([
     {
       name: "uses streamed Claude assistant text when the result envelope is missing",
diff --git a/src/agents/cli-output.ts b/src/agents/cli-output.ts
index 64d89ebfa726..243a7fada216 100644
--- a/src/agents/cli-output.ts
+++ b/src/agents/cli-output.ts
@@ -2263,6 +2263,7 @@ export function parseCliOutput(params: {
   raw: string;
   backend: CliBackendConfig;
   providerId: string;
+  parseJsonlEvent?: CliBackendParseJsonlEvent;
   outputMode?: "json" | "jsonl" | "text";
   fallbackSessionId?: string;
 }): CliOutput {
@@ -2271,7 +2272,20 @@ export function parseCliOutput(params: {
     return { text: params.raw.trim(), sessionId: params.fallbackSessionId };
   }
   if (outputMode === "jsonl") {
-    const parsed = parseCliJsonl(params.raw, params.backend, params.providerId);
+    let parsed: CliOutput | null;
+    if (params.parseJsonlEvent) {
+      const parser = createCliJsonlStreamingParser({
+        backend: params.backend,
+        providerId: params.providerId,
+        parseJsonlEvent: params.parseJsonlEvent,
+        onAssistantDelta: () => {},
+      });
+      parser.push(params.raw);
+      parser.finish();
+      parsed = parser.getOutput();
+    } else {
+      parsed = parseCliJsonl(params.raw, params.backend, params.providerId);
+    }
     if (parsed) {
       return parsed;
     }
diff --git a/src/agents/cli-runner/claude-live-session.capability.test.ts b/src/agents/cli-runner/claude-live-session.capability.test.ts
index 4ea5c097ed3c..7b5c10396065 100644
--- a/src/agents/cli-runner/claude-live-session.capability.test.ts
+++ b/src/agents/cli-runner/claude-live-session.capability.test.ts
@@ -1,5 +1,6 @@
 /** Claude live-session capability negotiation and input ownership tests. */
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import type { CliBackendParseJsonlEvent } from "../../plugins/cli-backend.types.js";
 import type { getProcessSupervisor } from "../../process/supervisor/index.js";
 import { buildClaudeLiveRunContext, mockClaudeLiveRun } from "../cli-runner.test-helpers.js";
 import { supervisorSpawnMock } from "../cli-runner.test-support.js";
@@ -36,13 +37,21 @@ function getProcessSupervisorForTest() {
   };
 }
 
-function startLiveTurn(runId: string, useResume: boolean) {
+function startLiveTurn(
+  runId: string,
+  useResume: boolean,
+  options: {
+    onPhase?: (phase: "send" | "resolve") => void;
+    parseJsonlEvent?: CliBackendParseJsonlEvent;
+  } = {},
+) {
   const context = buildClaudeLiveRunContext({
     runId,
     timeoutMs: 60_000,
     liveSessionRequirement,
     backend: { resumeArgs: ["-p", "--resume", "{sessionId}"] },
   });
+  context.backendResolved.parseJsonlEvent = options.parseJsonlEvent;
   return runClaudeLiveSessionTurn({
     context,
     args: context.preparedBackend.backend.args ?? [],
@@ -52,11 +61,69 @@ function startLiveTurn(runId: string, useResume: boolean) {
     noOutputTimeoutMs: 5_000,
     getProcessSupervisor: getProcessSupervisorForTest,
     onAssistantDelta: () => {},
+    onPhase: options.onPhase,
     cleanup: async () => {},
   });
 }
 
 describe("Claude live-session capability negotiation", () => {
+  it("rejects a malformed terminal result before background-task deferral", async () => {
+    const parseJsonlEvent = vi.fn<CliBackendParseJsonlEvent>((line) => {
+      const parsed = JSON.parse(line) as { type?: string; result?: string };
+      if (parsed.type !== "result" || !parsed.result?.includes('<invoke name="Bash">')) {
+        return null;
+      }
+      return {
+        kind: "result",
+        errorText:
+          "Claude CLI returned malformed tool output (invalid request format): raw tool protocol appeared as assistant text.",
+      };
+    });
+    const phases: Array<"send" | "resolve"> = [];
+    const fixture = mockClaudeLiveRun(supervisorSpawnMock, {
+      events: [
+        {
+          type: "system",
+          subtype: "init",
+          session_id: "live-malformed",
+          capabilities: ["msg_lifecycle_v1"],
+        },
+        {
+          type: "system",
+          subtype: "background_tasks_changed",
+          tasks: [{ task_id: "task-1", task_type: "local_agent", description: "still running" }],
+        },
+        {
+          type: "result",
+          subtype: "success",
+          session_id: "live-malformed",
+          result: [
+            '<invoke name="Bash">',
+            '<parameter name="command">pwd</parameter>',
+            "</invoke>",
+          ].join("\n"),
+        },
+      ],
+    });
+
+    await expect(
+      startLiveTurn("run-malformed-result", false, {
+        parseJsonlEvent,
+        onPhase: (phase) => phases.push(phase),
+      }),
+    ).rejects.toMatchObject({
+      name: "FailoverError",
+      reason: "format",
+      status: 400,
+      rawError: expect.stringContaining("raw tool protocol appeared as assistant text"),
+    });
+    expect(phases).toEqual(["resolve"]);
+    expect(fixture.writes.filter((line) => line.includes('"type":"user"'))).toHaveLength(1);
+    expect(
+      parseJsonlEvent.mock.calls.filter(([line]) => line.includes('"type":"result"')),
+    ).toHaveLength(1);
+  });
+
   it.each([
     { label: "fresh", useResume: false },
     { label: "resumed", useResume: true },
diff --git a/src/agents/cli-runner/claude-live-session.ts b/src/agents/cli-runner/claude-live-session.ts
index 8229f3ded393..01ba10d640ec 100644
--- a/src/agents/cli-runner/claude-live-session.ts
+++ b/src/agents/cli-runner/claude-live-session.ts
@@ -31,6 +31,7 @@ import { KeyedAsyncQueue } from "../../plugin-sdk/keyed-async-queue.js";
 import type {
   CliBackendConfig,
   CliBackendLiveSessionRequirement,
+  CliBackendParseJsonlEvent,
 } from "../../plugins/cli-backend.types.js";
 import {
   LEGACY_IMPLICIT_AGENT_ID,
@@ -79,6 +80,7 @@ type ProcessSupervisor = ReturnType<
 type ManagedRun = Awaited<ReturnType<ProcessSupervisor["spawn"]>>;
 type ClaudeLiveTurn = {
   backend: CliBackendConfig;
+  parseJsonlEvent?: CliBackendParseJsonlEvent;
   diagnosticRefs: ClaudeLiveDiagnosticRefs;
   /** Enclosing run abort signal; authoritative for tool terminal reason on turn failure. */
   abortSignal?: AbortSignal;
@@ -1410,6 +1412,7 @@ function handleClaudeLiveLine(session: ClaudeLiveSession, line: string): void {
       raw,
       backend: turn.backend,
       providerId: session.providerId,
+      parseJsonlEvent: turn.parseJsonlEvent,
       outputMode: "jsonl",
       fallbackSessionId: turn.sessionId,
     });
@@ -1685,6 +1688,7 @@ function createTurn(params: {
 }): ClaudeLiveTurn {
   const turn: ClaudeLiveTurn = {
     backend: params.context.preparedBackend.backend,
+    parseJsonlEvent: params.context.backendResolved.parseJsonlEvent,
     diagnosticRefs: {
       runId: params.context.params.runId,
       sessionId: params.context.params.sessionId,
@@ -1710,6 +1714,7 @@ function createTurn(params: {
     streamingParser: createCliJsonlStreamingParser({
       backend: params.context.preparedBackend.backend,
       providerId: params.context.backendResolved.id,
+      parseJsonlEvent: params.context.backendResolved.parseJsonlEvent,
       onAssistantDelta: params.onAssistantDelta,
       onThinkingDelta: params.onThinkingDelta,
       onThinkingProgress: params.onThinkingProgress,