diff --git a/src/web/response-viewer-transcript.ts b/src/web/response-viewer-transcript.ts
new file mode 100644
index 00000000..1404aa81
--- /dev/null
+++ b/src/web/response-viewer-transcript.ts
@@ -0,0 +1,311 @@
+export type ResponseViewerTranscriptKind = 'prompt' | 'response' | 'status' | 'tool';
+
+export interface ResponseViewerTranscriptBlock {
+  kind: ResponseViewerTranscriptKind;
+  label: 'Prompt' | 'Response' | 'Status' | 'Tool';
+  text: string;
+}
+
+const EXTERNAL_CLI_MODES = new Set(['codex', 'gemini', 'opencode', 'antigravity']);
+
+function isPromptLine(line: string): boolean {
+  return /^\s*›\s*/.test(line);
+}
+
+function normalizeDividerStatusLine(line: string): string | null {
+  const trimmed = line.trim();
+  const matched = trimmed.match(/^[─-]+\s*(.+?)\s*[─-]{3,}$/);
+  if (!matched) return null;
+  return matched[1]?.trim() || null;
+}
+
+function isDividerOnlyLine(line: string): boolean {
+  return /^[\s─-]{8,}$/.test(line.trim());
+}
+
+// COD-227: unambiguous Codex tool-call markers. These only ever appear as internal
+// activity, never as ordinary assistant prose, so they are always a Tool block.
+function isToolActivityMarker(line: string): boolean {
+  return /^\s*[•*-]\s+(Calling|Called)\b/.test(line.trim());
+}
+
+// COD-227: action verbs that ALSO occur in ordinary assistant prose (e.g.
+// "• Created COD-226: …"). These are a Tool header only when corroborated by a
+// box-drawing result tree on the next non-blank line (see the caller); the verb
+// alone is not sufficient.
+function isToolVerbBullet(line: string): boolean {
+  return /^\s*[•*-]\s+(Explored|Viewed|Read|Edited|Updated|Created|Deleted|Ran|Searched|Opened|Listed|Found|Applied|Patched|Used|Wrote|Executed|Modified|Analyzed|Compared|Fetched|Installed)\b/.test(
+    line.trim()
+  );
+}
+
+// A genuine Codex tool block renders its result as a box-drawing tree (└ │ ├).
+function isBoxDrawingLine(line: string): boolean {
+  return /^[│├└]/.test(line.trim());
+}
+
+// Look past blank lines from `fromIndex + 1` for the next non-blank line and report
+// whether it is a box-drawing tool-result line — the signal that a verb bullet is a
+// real tool block rather than assistant prose that happens to start with a verb.
+function nextNonBlankIsBoxDrawing(lines: string[], fromIndex: number): boolean {
+  for (let j = fromIndex + 1; j < lines.length; j += 1) {
+    const trimmed = (lines[j] || '').trim();
+    if (!trimmed) continue;
+    return isBoxDrawingLine(trimmed);
+  }
+  return false;
+}
+
+function isToolContinuationLine(line: string, currentKind: ResponseViewerTranscriptKind | null): boolean {
+  if (currentKind !== 'tool') return false;
+  const trimmed = line.trimEnd();
+  if (!trimmed) return true;
+  return /^\s*[│├└]/.test(trimmed) || /^\s{2,}\S/.test(line);
+}
+
+function isStatusLine(line: string, mode: string): boolean {
+  if (!EXTERNAL_CLI_MODES.has(mode)) return false;
+  const trimmed = line.trim();
+  if (!trimmed) return false;
+  if (normalizeDividerStatusLine(trimmed)) return true;
+  if (/^(model|directory):\s+/i.test(trimmed)) return true;
+  if (/\bContext\b.*\bleft\b/i.test(trimmed)) return true;
+  if (/\b\/model to change\b/i.test(trimmed)) return true;
+  if (/\bReady\b/i.test(trimmed) && /·/.test(trimmed)) return true;
+  if (/^(gpt|o\d|claude|gemini)\b/i.test(trimmed) && /·/.test(trimmed)) return true;
+  if (/^Tip:/i.test(trimmed)) return true;
+  if (/^\s*[•*-]\s+(Working|Thinking|Loading|Starting\b|Waiting\b)/i.test(trimmed)) return true;
+  return false;
+}
+
+function isStandaloneMarkdownLine(line: string): boolean {
+  const trimmed = line.trim();
+  if (!trimmed) return false;
+  if (/^#{1,6}\s/.test(trimmed)) return true;
+  if (/^>\s/.test(trimmed)) return true;
+  if (/^(```|~~~)/.test(trimmed)) return true;
+  if (/^[-*+]\s/.test(trimmed)) return true;
+  if (/^\d+[.)]\s/.test(trimmed)) return true;
+  if (/^\|/.test(trimmed)) return true;
+  if (/^\s{4,}\S/.test(line)) return true;
+  return false;
+}
+
+function shouldJoinWrappedLine(previous: string, next: string): boolean {
+  const prev = previous.trimEnd();
+  const curr = next.trim();
+  if (!prev || !curr) return false;
+  if (/[.!?]$/.test(prev)) return false;
+  if (/[:;]$/.test(prev)) return false;
+  if (isStandaloneMarkdownLine(curr)) return false;
+  if (/^[a-z(]/.test(curr)) return true;
+  if (prev.length >= 72 && /^[A-Za-z0-9"'(]/.test(curr)) return true;
+  return false;
+}
+
+function normalizeWrappedText(lines: string[]): string {
+  const out: string[] = [];
+  let paragraph = '';
+
+  const flushParagraph = () => {
+    if (!paragraph) return;
+    out.push(paragraph);
+    paragraph = '';
+  };
+
+  for (const rawLine of lines) {
+    const line = rawLine.trimEnd();
+    const trimmed = line.trim();
+    if (!trimmed) {
+      flushParagraph();
+      if (out[out.length - 1] !== '') out.push('');
+      continue;
+    }
+    if (isStandaloneMarkdownLine(line)) {
+      flushParagraph();
+      out.push(trimmed);
+      continue;
+    }
+    if (!paragraph) {
+      paragraph = trimmed;
+      continue;
+    }
+    if (shouldJoinWrappedLine(paragraph, trimmed)) {
+      paragraph += ` ${trimmed}`;
+      continue;
+    }
+    flushParagraph();
+    paragraph = trimmed;
+  }
+
+  flushParagraph();
+  return out
+    .join('\n')
+    .replace(/\n{3,}/g, '\n\n')
+    .trim();
+}
+
+function cleanTerminalTranscript(buffer: string): string {
+  // Stripping ANSI/OSC/DCS escape sequences and stray C0/C1 control bytes
+  // legitimately requires control characters in these patterns.
+  /* eslint-disable no-control-regex */
+  return String(buffer || '')
+    .replace(/\x1b\[[\x30-\x3F]*[\x20-\x2F]*[\x40-\x7E]/g, '')
+    .replace(/\x1b\][^\x07\x1b]*(?:\x07|\x1b\\)/g, '')
+    .replace(/\x1b[PX^_][^\x1b]*\x1b\\/g, '')
+    .replace(/\x1b[NO()][A-Z0-9]?/g, '')
+    .replace(/\x1b[>=<78cDEHM]/g, '')
+    .replace(/[\x00-\x08\x0b\x0c\x0e-\x1f\x7f]/g, '')
+    .replace(/\r\n/g, '\n')
+    .replace(/\r/g, '\n')
+    .replace(/[ \t]+$/gm, '')
+    .trim();
+  /* eslint-enable no-control-regex */
+}
+
+function trimLeadingStartup(lines: string[]): string[] {
+  let index = 0;
+  while (index < lines.length) {
+    const line = lines[index] || '';
+    const trimmed = line.trim();
+    if (!trimmed) {
+      index += 1;
+      continue;
+    }
+    if (/^[╭╰│─].*[╮╯│]?$/.test(trimmed)) {
+      index += 1;
+      continue;
+    }
+    if (/^>_\s*OpenAI Codex/i.test(trimmed)) {
+      index += 1;
+      continue;
+    }
+    if (/^(model|directory):\s+/i.test(trimmed)) {
+      index += 1;
+      continue;
+    }
+    break;
+  }
+  return lines.slice(index);
+}
+
+function pushBlock(
+  blocks: ResponseViewerTranscriptBlock[],
+  kind: ResponseViewerTranscriptKind | null,
+  lines: string[]
+): void {
+  if (!kind || lines.length === 0) return;
+  const normalizedLines =
+    kind === 'status'
+      ? lines.map((line) => normalizeDividerStatusLine(line) || line.trim()).filter((line) => line.length > 0)
+      : lines;
+  const text =
+    kind === 'tool' || kind === 'status'
+      ? normalizedLines
+          .join('\n')
+          .replace(/\n{3,}/g, '\n\n')
+          .trim()
+      : normalizeWrappedText(normalizedLines);
+  if (!text) return;
+  const label = (kind.charAt(0).toUpperCase() + kind.slice(1)) as ResponseViewerTranscriptBlock['label'];
+  blocks.push({ kind, label, text });
+}
+
+export function isExternalCliTranscriptMode(mode: string | null | undefined): boolean {
+  return EXTERNAL_CLI_MODES.has(String(mode || ''));
+}
+
+export function parseExternalCliTranscript(
+  buffer: string,
+  mode: string | null | undefined
+): ResponseViewerTranscriptBlock[] {
+  const resolvedMode = String(mode || '');
+  if (!isExternalCliTranscriptMode(resolvedMode)) return [];
+
+  const cleaned = cleanTerminalTranscript(buffer);
+  if (!cleaned) return [];
+
+  const lines = trimLeadingStartup(cleaned.split('\n'));
+  const blocks: ResponseViewerTranscriptBlock[] = [];
+  let currentKind: ResponseViewerTranscriptKind | null = null;
+  let currentLines: string[] = [];
+
+  const flush = () => {
+    pushBlock(blocks, currentKind, currentLines);
+    currentKind = null;
+    currentLines = [];
+  };
+
+  for (let i = 0; i < lines.length; i += 1) {
+    const line = lines[i] ?? '';
+    // COD-226: within a prompt, the 2-space Codex gutter is authoritative. Blank
+    // lines and gutter-indented (2+ leading spaces) continuation lines stay in the
+    // Prompt block ahead of every structural detector below, so multiline prompts —
+    // including bullets, indented dividers, and literal › lines — are not
+    // misclassified as responses. Only a non-blank, non-gutter line ends the prompt
+    // and falls through (a column-0 › then opens a NEW prompt).
+    if (currentKind === 'prompt') {
+      if (!line.trim()) {
+        currentLines.push('');
+        continue;
+      }
+      if (/^ {2,}\S/.test(line)) {
+        currentLines.push(line);
+        continue;
+      }
+    }
+
+    if (isDividerOnlyLine(line)) {
+      flush();
+      continue;
+    }
+
+    if (isPromptLine(line)) {
+      flush();
+      currentKind = 'prompt';
+      currentLines = [line.replace(/^\s*›\s*/, '').trim()];
+      continue;
+    }
+
+    // COD-227: • Calling / • Called are always tool markers; the other action verbs
+    // are a tool header only when a box-drawing result tree follows on the next
+    // non-blank line — otherwise the verb bullet is ordinary assistant prose.
+    if (isToolActivityMarker(line) || (isToolVerbBullet(line) && nextNonBlankIsBoxDrawing(lines, i))) {
+      if (currentKind !== 'tool') flush();
+      currentKind = 'tool';
+      currentLines.push(line.trimEnd());
+      continue;
+    }
+
+    if (isToolContinuationLine(line, currentKind)) {
+      currentLines.push(line.trimEnd());
+      continue;
+    }
+
+    if (isStatusLine(line, resolvedMode)) {
+      if (currentKind !== 'status') flush();
+      currentKind = 'status';
+      currentLines.push(line.trim());
+      continue;
+    }
+
+    if (!line.trim()) {
+      currentLines.push('');
+      continue;
+    }
+
+    if (currentKind !== 'response') flush();
+    currentKind = 'response';
+    currentLines.push(line);
+  }
+
+  flush();
+  return blocks.filter((block) => block.text.trim().length > 0);
+}
+
+export function getLastTranscriptResponse(blocks: ResponseViewerTranscriptBlock[]): string {
+  for (let i = blocks.length - 1; i >= 0; i -= 1) {
+    if (blocks[i]?.kind === 'response') return blocks[i].text;
+  }
+  return '';
+}
diff --git a/src/web/routes/session-routes.ts b/src/web/routes/session-routes.ts
index 98ea4e7c..aa012142 100644
--- a/src/web/routes/session-routes.ts
+++ b/src/web/routes/session-routes.ts
@@ -131,6 +131,11 @@ import {
   toSessionDocker,
 } from '../../docker-hosts.js';
 import { LRUMap } from '../../utils/lru-map.js';
+import {
+  getLastTranscriptResponse,
+  isExternalCliTranscriptMode,
+  parseExternalCliTranscript,
+} from '../response-viewer-transcript.js';
 
 // Path to linked-cases registry (same file used by case-routes resolveCasePath)
 const LINKED_CASES_FILE = dataPath('linked-cases.json');
@@ -1898,6 +1903,22 @@ export function registerSessionRoutes(
       return await readCodexLastResponse(session, codexQuery.context === 'full');
     }
 
+    // OpenCode / Gemini / Antigravity render their own TUIs and write no Claude
+    // transcript, so the scan below finds nothing and the response viewer renders
+    // permanently empty for them. Segment the terminal buffer instead — the pane
+    // IS the transcript for these CLIs. Codex is already handled above, where a
+    // real rollout file is the better source.
+    if (isExternalCliTranscriptMode(session.mode)) {
+      const externalQuery = req.query as { context?: string };
+      const blocks = parseExternalCliTranscript(session.terminalBuffer, session.mode);
+      return {
+        text: getLastTranscriptResponse(blocks),
+        timestamp: '',
+        hasContext: blocks.length > 0,
+        messages: externalQuery.context === 'full' ? blocks : undefined,
+      };
+    }
+
     // Scan ~/.claude/projects/*/ for the transcript file
     const projectsDir = join(process.env.HOME || '/tmp', '.claude', 'projects');
 
diff --git a/test/response-viewer-transcript.test.ts b/test/response-viewer-transcript.test.ts
new file mode 100644
index 00000000..818c69d7
--- /dev/null
+++ b/test/response-viewer-transcript.test.ts
@@ -0,0 +1,323 @@
+import { describe, expect, it } from 'vitest';
+import { getLastTranscriptResponse, parseExternalCliTranscript } from '../src/web/response-viewer-transcript.js';
+
+describe('response viewer transcript parser', () => {
+  it('extracts structured COD transcript blocks and keeps labeled status/tool entries', () => {
+    const transcript = `
+╭──────────────────────────────────────────────────────╮
+│ >_ OpenAI Codex (v0.143.0)                           │
+│ model:     gpt-5.4 medium   /model to change         │
+│ directory: /mnt/c/Users/aakhter/.../kb              │
+╰──────────────────────────────────────────────────────╯
+
+Tip: Use /side to start a side conversation in a temporary fork without polluting the main thread.
+
+› i need to create a naming recommendation for project helix
+
+gpt-5.4 medium · kb · main · Ready · Context 100% left
+
+• Explored
+  └ Read SKILL.md
+
+Subject: Naming Recommendation for Project Helix
+
+The product helps customers move virtual machine workloads between hypervisors while keeping operations
+stable. It improves visibility into application dependencies, supports pre-migration validation, and reduces
+the risk
+and effort involved in moving workloads.
+
+› Improve documentation in @filename
+
+gpt-5.4 medium · kb · main · Ready · Context 92% left
+`.trim();
+
+    const blocks = parseExternalCliTranscript(transcript, 'codex');
+
+    expect(blocks.map((block) => block.kind)).toEqual([
+      'status',
+      'prompt',
+      'status',
+      'tool',
+      'response',
+      'prompt',
+      'status',
+    ]);
+    expect(blocks[0]?.label).toBe('Status');
+    expect(blocks[3]?.label).toBe('Tool');
+    expect(blocks[4]?.text).toContain('reduces the risk and effort involved');
+    expect(blocks[4]?.text).not.toContain('reduces\nthe risk');
+  });
+
+  it('returns the most recent completed response when the last block is a new prompt', () => {
+    const transcript = `
+› say again
+
+Final polished answer
+With two lines
+
+› Improve documentation in @filename
+
+gpt-5.4 medium · kb · main · Ready · Context 92% left
+`.trim();
+
+    const blocks = parseExternalCliTranscript(transcript, 'codex');
+
+    expect(getLastTranscriptResponse(blocks)).toBe('Final polished answer\nWith two lines');
+  });
+
+  it('drops box-drawing dividers from the last response and treats worked-for lines as status', () => {
+    const transcript = `
+────────────────────────────────────────────────────────────────────────
+
+• The launcher supports CODEMAN_APP_DIR, so I can deploy this exact worktree without merging it back first.
+
+────────────────────────────────────────────────────────────────────────
+
+• Deployed.
+
+The local Codeman service is now running from the worktree at app/.worktrees/cod-215-response-viewer on
+commit 8bbcf77bafbdbf01a34653386c256b685898ad06.
+
+Verified:
+
+- process pid: 2708947
+- HTTPS health: https://127.0.0.1:3000/ returned 401 as expected
+
+One detail: I had to restart it outside the sandbox because the sandboxed launch path could not see tmux.
+
+─ Worked for 1m 51s ───────────────────────────────────────────────────
+
+› what are these lines in the middle column?
+`.trim();
+
+    const blocks = parseExternalCliTranscript(transcript, 'codex');
+
+    expect(getLastTranscriptResponse(blocks)).toContain('• Deployed.');
+    expect(getLastTranscriptResponse(blocks)).not.toContain('────────────────');
+    expect(getLastTranscriptResponse(blocks)).not.toContain('Worked for 1m 51s');
+    expect(blocks.some((block) => block.kind === 'status' && block.text === 'Worked for 1m 51s')).toBe(true);
+  });
+
+  // COD-226: multiline prompt continuations (2-space Codex gutter) must stay in the
+  // Prompt block, not be misclassified as Response. The gutter is authoritative ahead
+  // of every structural detector (divider, prompt-marker, tool, status).
+  describe('COD-226 multiline prompt gutter is authoritative', () => {
+    it('keeps bullet/prose continuations and internal blank lines in the Prompt block', () => {
+      const transcript = `
+› i think we can improve this slide. or maybe a follow on slide. here is what i'm thinking:
+  * left hand side: current AI stack (frontier model, cloud hosted, sovereign concerns)
+  right hand -> future enterprise stack: frontier model (optional, cloud), on-prem model router, OSS models
+
+  make the point that the right hand side addresses the concerns.
+
+gpt-5.4 medium · kb · main · Ready · Context 100% left
+
+• Explored
+  └ Read SKILL.md
+
+Here is the actual assistant answer that starts at column zero and is a real response.
+
+› next prompt
+`.trim();
+
+      const blocks = parseExternalCliTranscript(transcript, 'codex');
+      const promptBlocks = blocks.filter((b) => b.kind === 'prompt');
+
+      // Exactly two prompts, and the first holds the whole multiline prompt.
+      expect(promptBlocks).toHaveLength(2);
+      expect(promptBlocks[0]?.text).toContain('left hand side');
+      expect(promptBlocks[0]?.text).toContain('right hand');
+      expect(promptBlocks[0]?.text).toContain('make the point that the right hand side');
+
+      // The continuation must NOT have leaked into a Response block.
+      const responseBlocks = blocks.filter((b) => b.kind === 'response');
+      expect(responseBlocks.some((b) => b.text.includes('make the point'))).toBe(false);
+      expect(getLastTranscriptResponse(blocks)).toContain('actual assistant answer');
+      expect(getLastTranscriptResponse(blocks)).not.toContain('make the point');
+    });
+
+    it('does not let an indented divider inside a prompt flush the Prompt block', () => {
+      const transcript = `
+› compare these two layouts
+  first layout uses a single column
+  ────────────────────────────
+  second layout uses two columns
+
+The response begins here at column zero.
+`.trim();
+
+      const blocks = parseExternalCliTranscript(transcript, 'codex');
+      const promptBlocks = blocks.filter((b) => b.kind === 'prompt');
+
+      expect(promptBlocks).toHaveLength(1);
+      expect(promptBlocks[0]?.text).toContain('first layout');
+      expect(promptBlocks[0]?.text).toContain('second layout uses two columns');
+      expect(getLastTranscriptResponse(blocks)).toBe('The response begins here at column zero.');
+    });
+
+    it('treats a gutter-indented literal › as prompt content, not a new prompt', () => {
+      const transcript = `
+› here is my question about the ui
+  › should this arrow start a new prompt?
+  no it should not — it is part of my question
+
+Answer at column zero.
+`.trim();
+
+      const blocks = parseExternalCliTranscript(transcript, 'codex');
+      const promptBlocks = blocks.filter((b) => b.kind === 'prompt');
+
+      // The gutter-indented › must NOT open a second prompt.
+      expect(promptBlocks).toHaveLength(1);
+      expect(promptBlocks[0]?.text).toContain('here is my question');
+      expect(promptBlocks[0]?.text).toContain('no it should not');
+      expect(getLastTranscriptResponse(blocks)).toBe('Answer at column zero.');
+    });
+
+    // The two exact live roadmap-tab examples from the ticket (AC: use both verbatim).
+    it('live example 1: two-line prompt keeps the gutter continuation in the Prompt block', () => {
+      const transcript = `
+› create uid for each feature so it's easy to ref.
+  for the p200 - why is diffentiation only 2/5?
+`.trim();
+
+      const blocks = parseExternalCliTranscript(transcript, 'codex');
+      const promptBlocks = blocks.filter((b) => b.kind === 'prompt');
+
+      expect(promptBlocks).toHaveLength(1);
+      expect(promptBlocks[0]?.text).toContain('create uid for each feature');
+      expect(promptBlocks[0]?.text).toContain('for the p200 - why is diffentiation only 2/5?');
+      // The continuation must not have leaked into a Response block.
+      expect(blocks.some((b) => b.kind === 'response')).toBe(false);
+    });
+
+    it('live example 2: five-line prompt (bullet + prose + blank + prose) stays one Prompt block', () => {
+      const transcript = `
+› i think we can improve this slide. or maybe a follow on slide. here is what i'm thinking:
+  * left hand side... current AI stack: (frontier model), large component cloud hosted, soverign concerns etc.
+  right hand -> future-enterprise-stack: frontier-model (optional, in cloud), on-prem: model router, OSS models, rest of stack (gpus, data, etc.)
+
+  make the point that the right hand side addresses the concerns.
+`.trim();
+
+      const blocks = parseExternalCliTranscript(transcript, 'codex');
+      const promptBlocks = blocks.filter((b) => b.kind === 'prompt');
+
+      expect(promptBlocks).toHaveLength(1);
+      expect(promptBlocks[0]?.text).toContain('left hand side');
+      expect(promptBlocks[0]?.text).toContain('right hand -> future-enterprise-stack');
+      expect(promptBlocks[0]?.text).toContain('make the point that the right hand side addresses the concerns');
+      expect(blocks.some((b) => b.kind === 'response')).toBe(false);
+    });
+
+    it('still separates a single-line prompt from a column-zero response (no regression)', () => {
+      const transcript = `
+› say again
+
+Final polished answer at column zero.
+
+› next
+`.trim();
+
+      const blocks = parseExternalCliTranscript(transcript, 'codex');
+      const promptBlocks = blocks.filter((b) => b.kind === 'prompt');
+
+      expect(promptBlocks).toHaveLength(2);
+      expect(promptBlocks[0]?.text).toBe('say again');
+      expect(getLastTranscriptResponse(blocks)).toBe('Final polished answer at column zero.');
+    });
+  });
+
+  // COD-227: Last Response must return the final assistant answer, not tool logs.
+  // A response bullet beginning with a tool-like verb (• Created …) must not be
+  // classified as Tool, and genuine • Calling / • Called blocks must be classified
+  // as Tool. Disambiguator: a verb-bullet is a tool header only when followed by a
+  // box-drawing result tree (└│├); Calling/Called are always tool markers.
+  describe('COD-227 tool-header vs response disambiguation', () => {
+    const MINIMAL_REPRO = `
+› new jira issue
+
+• The fresh read shows a formatting problem.
+
+• Calling
+└ atlassian.jira_update_issue({})
+
+• Called atlassian.jira_get_issue({})
+└ { result: true }
+
+• Created COD-226: View Response → More misclassifies multiline prompt continuations as responses.
+
+  It includes:
+
+  - Two concrete failures
+  - Regression-test criteria
+`.trim();
+
+    it('returns the final • Created … answer, not the Jira Calling/Called tool log', () => {
+      const blocks = parseExternalCliTranscript(MINIMAL_REPRO, 'codex');
+      const last = getLastTranscriptResponse(blocks);
+
+      expect(last).toContain('Created COD-226');
+      expect(last).toContain('Two concrete failures');
+      // Must exclude tool invocations, raw results, and earlier commentary.
+      expect(last).not.toContain('atlassian.jira');
+      expect(last).not.toContain('Calling');
+      expect(last).not.toContain('Called');
+      expect(last).not.toContain('fresh read');
+    });
+
+    it('classifies genuine • Calling / • Called (with box-drawing results) as Tool', () => {
+      const blocks = parseExternalCliTranscript(MINIMAL_REPRO, 'codex');
+      const toolText = blocks
+        .filter((b) => b.kind === 'tool')
+        .map((b) => b.text)
+        .join('\n');
+
+      expect(toolText).toContain('Calling');
+      expect(toolText).toContain('Called');
+      expect(toolText).toContain('atlassian.jira_update_issue');
+      // The final answer must not have been swallowed into the tool block.
+      expect(toolText).not.toContain('Created COD-226');
+    });
+
+    it('labels the repro chronologically: Prompt, Response (commentary), Tool, Response (final)', () => {
+      const blocks = parseExternalCliTranscript(MINIMAL_REPRO, 'codex');
+
+      expect(blocks.map((b) => b.kind)).toEqual(['prompt', 'response', 'tool', 'response']);
+      expect(blocks[1]?.text).toContain('fresh read');
+      expect(blocks[3]?.text).toContain('Created COD-226');
+    });
+
+    it('does not classify a verb-prefixed prose bullet as Tool when no result tree follows', () => {
+      const transcript = `
+› do it
+
+• Created COD-999: a brand new issue with a descriptive title.
+
+  Follow-up prose that belongs to the same answer.
+`.trim();
+
+      const blocks = parseExternalCliTranscript(transcript, 'codex');
+
+      expect(blocks.some((b) => b.kind === 'tool')).toBe(false);
+      expect(getLastTranscriptResponse(blocks)).toContain('Created COD-999');
+      expect(getLastTranscriptResponse(blocks)).toContain('Follow-up prose');
+    });
+
+    it('does not regress a genuine verb tool block that has a box-drawing continuation', () => {
+      const transcript = `
+› look around
+
+• Explored
+  └ Read SKILL.md
+
+Here is the assistant answer at column zero.
+`.trim();
+
+      const blocks = parseExternalCliTranscript(transcript, 'codex');
+
+      expect(blocks.some((b) => b.kind === 'tool' && b.text.includes('Explored'))).toBe(true);
+      expect(getLastTranscriptResponse(blocks)).toBe('Here is the assistant answer at column zero.');
+    });
+  });
+});
diff --git a/test/routes/session-routes-external-cli-last-response.test.ts b/test/routes/session-routes-external-cli-last-response.test.ts
new file mode 100644
index 00000000..9853ea1c
--- /dev/null
+++ b/test/routes/session-routes-external-cli-last-response.test.ts
@@ -0,0 +1,160 @@
+/**
+ * @fileoverview Tests for the external-CLI branch of GET /api/sessions/:id/last-response.
+ *
+ * Uses app.inject() — no real HTTP ports needed.
+ * Port: N/A (app.inject doesn't open ports)
+ *
+ * OpenCode / Gemini / Antigravity render their own TUIs and never write a Claude
+ * transcript under ~/.claude/projects, so before this branch existed the handler
+ * fell through to the Claude scan, found nothing, and the response viewer was
+ * permanently empty for those modes. These tests pin:
+ *   - the pane buffer is segmented and the LAST response is returned
+ *   - ?context=full carries the parsed blocks, and the short form omits them
+ *   - a pane that has produced no output reports hasContext: false rather than 404ing
+ *   - Claude mode still takes the Claude path (regression guard)
+ */
+
+import { describe, it, expect, beforeEach } from 'vitest';
+import Fastify, { type FastifyInstance } from 'fastify';
+import fastifyCookie from '@fastify/cookie';
+import { createMockRouteContext, createMockSession, type MockRouteContext } from '../mocks/index.js';
+import { ApiErrorCode, httpStatusForErrorCode } from '../../src/types.js';
+import { registerSessionRoutes } from '../../src/web/routes/session-routes.js';
+
+interface LocalHarness {
+  app: FastifyInstance;
+  ctx: MockRouteContext;
+}
+
+/** Mirror of the production uniform-envelope hook (server.ts), as in the sibling suites. */
+async function createEnvelopeHarness(
+  registerFn: (app: FastifyInstance, ctx: MockRouteContext) => void
+): Promise<LocalHarness> {
+  const app = Fastify({ logger: false });
+  await app.register(fastifyCookie);
+
+  const ctx = createMockRouteContext();
+  registerFn(app, ctx);
+
+  app.addHook('preSerialization', (req, reply, payload: unknown, done) => {
+    if (!req.url.startsWith('/api')) return done(null, payload);
+    if (payload === null || typeof payload !== 'object') return done(null, payload);
+    if (Buffer.isBuffer(payload) || typeof (payload as { pipe?: unknown }).pipe === 'function') {
+      return done(null, payload);
+    }
+    const p = payload as { success?: unknown; errorCode?: unknown };
+    if (p.success === false) {
+      if (reply.statusCode === 200 && typeof p.errorCode === 'string') {
+        reply.code(httpStatusForErrorCode(p.errorCode as ApiErrorCode));
+      }
+      return done(null, payload);
+    }
+    if (p.success === true) return done(null, payload);
+    return done(null, { success: true, data: payload });
+  });
+
+  await app.ready();
+  return { app, ctx };
+}
+
+// A pane as one of these CLIs actually leaves it: banner, a `›` prompt line, a
+// status divider, a tool-activity marker, then the assistant's prose.
+const PANE = `
+╭──────────────────────────────────────────────────────╮
+│ >_ OpenCode                                          │
+│ directory: /workspace/project                        │
+╰──────────────────────────────────────────────────────╯
+
+› summarise the retry logic
+
+model · project · main · Ready · Context 100% left
+
+• Explored
+  └ Read src/retry.ts
+
+The retry helper backs off exponentially and gives up after five attempts.
+
+› now document it
+
+model · project · main · Ready · Context 92% left
+
+• Called write_file
+
+Documented the helper in docs/retry.md, including the five-attempt ceiling.
+`.trim();
+
+describe('GET /api/sessions/:id/last-response — external CLI panes', () => {
+  let harness: LocalHarness;
+  let session: ReturnType<typeof createMockSession>;
+
+  beforeEach(async () => {
+    harness = await createEnvelopeHarness(registerSessionRoutes);
+    session = harness.ctx._session;
+  });
+
+  async function lastResponse(full = false) {
+    const res = await harness.app.inject({
+      method: 'GET',
+      url: `/api/sessions/${session.id}/last-response${full ? '?context=full' : ''}`,
+    });
+    return { res, body: JSON.parse(res.body) };
+  }
+
+  for (const mode of ['opencode', 'gemini', 'antigravity'] as const) {
+    it(`returns the last assistant response from the ${mode} pane buffer`, async () => {
+      session.mode = mode;
+      session.terminalBuffer = PANE;
+
+      const { res, body } = await lastResponse();
+
+      expect(res.statusCode).toBe(200);
+      // The LAST response, not the first — the viewer shows the current turn.
+      expect(body.data.text).toContain('Documented the helper in docs/retry.md');
+      expect(body.data.text).not.toContain('backs off exponentially');
+      expect(body.data.hasContext).toBe(true);
+      // Short form stays short: blocks only travel under ?context=full.
+      expect(body.data.messages).toBeUndefined();
+    });
+  }
+
+  it('carries the parsed blocks under ?context=full', async () => {
+    session.mode = 'opencode';
+    session.terminalBuffer = PANE;
+
+    const { body } = await lastResponse(true);
+
+    const kinds = body.data.messages.map((block: { kind: string }) => block.kind);
+    expect(kinds).toContain('prompt');
+    expect(kinds).toContain('response');
+    expect(kinds).toContain('tool');
+    // Both user turns survive segmentation, so the viewer can show the exchange.
+    const prompts = body.data.messages.filter((b: { kind: string }) => b.kind === 'prompt');
+    expect(prompts).toHaveLength(2);
+    expect(prompts[1].text).toContain('now document it');
+  });
+
+  it('reports hasContext false for a pane that has produced no output', async () => {
+    session.mode = 'gemini';
+    // Session created but nothing rendered yet. Any non-prompt line counts as
+    // prose to the parser, so the empty pane is the honest no-context case.
+    session.terminalBuffer = '';
+
+    const { res, body } = await lastResponse();
+
+    expect(res.statusCode).toBe(200);
+    expect(body.data.text).toBe('');
+    expect(body.data.hasContext).toBe(false);
+  });
+
+  it('leaves Claude mode on the Claude transcript path', async () => {
+    // Regression guard: a claude pane must NOT be segmented off its terminal
+    // buffer, or a real transcript would be shadowed by scraped pane text.
+    session.mode = 'claude';
+    session.terminalBuffer = PANE;
+
+    const { res, body } = await lastResponse();
+
+    expect(res.statusCode).toBe(200);
+    expect(body.data.text).not.toContain('Documented the helper');
+  });
+});