diff --git a/apps/marketing/src/content/docs/guides/ai-features.md b/apps/marketing/src/content/docs/guides/ai-features.md
index aded351dd..a1f9ab3a5 100644
--- a/apps/marketing/src/content/docs/guides/ai-features.md
+++ b/apps/marketing/src/content/docs/guides/ai-features.md
@@ -18,10 +18,19 @@ Requires the `claude` CLI installed and authenticated. Uses Claude Code's full s
 
 **Models:**
 
-- Sonnet 4.6 (default)
+- Sonnet 5 (default)
+- Fable 5
+- Opus 5
+- Opus 4.8
+- Sonnet 4.6
+- Opus 4.7
 - Opus 4.6
 - Haiku 4.5
 
+Opus 4.8, Opus 4.7, Opus 4.6, and Sonnet 4.6 are also offered in `(1M)` context
+variants. The 5-series models use their 1M context window by default, so they
+have no separate variant.
+
 ### Codex (via Codex SDK)
 
 Requires the `codex` CLI installed and authenticated. The AI operates in a sandboxed read-only mode with the diff context injected as a system prompt prefix.
diff --git a/packages/ai/ai.test.ts b/packages/ai/ai.test.ts
index 8cf3e453a..e0ed678c7 100644
--- a/packages/ai/ai.test.ts
+++ b/packages/ai/ai.test.ts
@@ -888,6 +888,32 @@ describe("resolveSDKModel", () => {
     expect(resolveSDKModel("claude-sonnet-4-6[1m]", bedrockEnv)).toBe(SONNET_ARN);
   });
 
+  // Opus 5 is a bare alias like every other picker entry: it must NOT be
+  // mistaken for a cloud identifier (no `arn:` / `anthropic.` prefix), and the
+  // family matcher must still route it to the configured Opus ARN on
+  // Bedrock/Vertex. A matcher that keyed on "opus-4" would silently drop it.
+  test("maps the bare Opus 5 alias to the configured Opus ARN", () => {
+    expect(resolveSDKModel("claude-opus-5", bedrockEnv)).toBe(OPUS_ARN);
+    expect(
+      resolveSDKModel("claude-opus-5", {
+        CLAUDE_CODE_USE_VERTEX: "true",
+        ANTHROPIC_DEFAULT_OPUS_MODEL: OPUS_ARN,
+      }),
+    ).toBe(OPUS_ARN);
+  });
+
+  test("off Bedrock/Vertex: returns the Opus 5 alias unchanged", () => {
+    expect(resolveSDKModel("claude-opus-5", {})).toBe("claude-opus-5");
+  });
+
+  // Fable has no ANTHROPIC_DEFAULT_*_MODEL env var of its own (Claude Code
+  // only defines OPUS/SONNET/HAIKU), so on Bedrock it falls through to
+  // ANTHROPIC_MODEL rather than matching a family. Pinned so the fallthrough
+  // stays deliberate rather than looking like a missed family branch.
+  test("falls back to ANTHROPIC_MODEL for the Fable alias on Bedrock", () => {
+    expect(resolveSDKModel("claude-fable-5", bedrockEnv)).toBe(OPUS_ARN);
+  });
+
   test("passes through an identifier that is already an ARN", () => {
     expect(resolveSDKModel(SONNET_ARN, bedrockEnv)).toBe(SONNET_ARN);
   });
diff --git a/packages/ai/providers/claude-agent-sdk.ts b/packages/ai/providers/claude-agent-sdk.ts
index 3af4e3068..c4ea45c9a 100644
--- a/packages/ai/providers/claude-agent-sdk.ts
+++ b/packages/ai/providers/claude-agent-sdk.ts
@@ -165,6 +165,7 @@ export class ClaudeAgentSDKProvider implements AIProvider {
   };
   readonly models = [
     { id: 'claude-fable-5', label: 'Fable 5' },
+    { id: 'claude-opus-5', label: 'Opus 5' },
     { id: 'claude-opus-4-8', label: 'Opus 4.8' },
     { id: 'claude-opus-4-8[1m]', label: 'Opus 4.8 (1M)' },
     { id: 'claude-sonnet-5', label: 'Sonnet 5', default: true },
diff --git a/packages/server/agent-review-message.test.ts b/packages/server/agent-review-message.test.ts
index 8554123e4..b30e91589 100644
--- a/packages/server/agent-review-message.test.ts
+++ b/packages/server/agent-review-message.test.ts
@@ -286,6 +286,16 @@ describe("getLocalDiffInstruction", () => {
 });
 
 describe("buildClaudeCommand", () => {
+  test("defaults to Opus 5 when the caller passes no model", () => {
+    const command = buildClaudeCommand("review").command;
+    expect(command[command.indexOf("--model") + 1]).toBe("claude-opus-5");
+  });
+
+  test("still honours an explicitly requested model", () => {
+    const command = buildClaudeCommand("review", "claude-sonnet-5").command;
+    expect(command[command.indexOf("--model") + 1]).toBe("claude-sonnet-5");
+  });
+
   test("allows read-only JJ commands", () => {
     const command = buildClaudeCommand("review").command;
     const allowedTools = command[command.indexOf("--allowedTools") + 1];
diff --git a/packages/server/claude-review.ts b/packages/server/claude-review.ts
index 28fe57aef..98b6914a7 100644
--- a/packages/server/claude-review.ts
+++ b/packages/server/claude-review.ts
@@ -217,7 +217,7 @@ export interface ClaudeCommandResult {
  * Build the `claude -p` command. Prompt is passed via stdin, not as a
  * positional arg — avoids quoting issues, argv limits, and variadic flag conflicts.
  */
-export function buildClaudeCommand(prompt: string, model: string = "claude-opus-4-7", effort?: string): ClaudeCommandResult {
+export function buildClaudeCommand(prompt: string, model: string = "claude-opus-5", effort?: string): ClaudeCommandResult {
   const allowedTools = [
     "Agent", "Read", "Glob", "Grep",
     // GitHub CLI
diff --git a/packages/ui/components/AgentsTab.test.ts b/packages/ui/components/AgentsTab.test.ts
index 07c618905..722ef6884 100644
--- a/packages/ui/components/AgentsTab.test.ts
+++ b/packages/ui/components/AgentsTab.test.ts
@@ -1,8 +1,35 @@
 import { describe, expect, test } from "bun:test";
-import { CODEX_MODELS, codexReasoningOptions } from "./AgentsTab";
+import { CLAUDE_MODELS, CODEX_MODELS, TOUR_CLAUDE_MODELS, codexReasoningOptions } from "./AgentsTab";
 
 const catalogEntry = (value: string) => CODEX_MODELS.find((m) => m.value === value);
 
+describe("CLAUDE_MODELS catalog", () => {
+  test("offers the current 5-series flagships", () => {
+    for (const value of ["claude-fable-5", "claude-opus-5", "claude-sonnet-5"]) {
+      expect(CLAUDE_MODELS.some((m) => m.value === value)).toBe(true);
+    }
+    expect(CLAUDE_MODELS.find((m) => m.value === "claude-opus-5")?.label).toBe("Opus 5");
+  });
+
+  // The 5-series models are 1M-context by default, so they carry no `[1m]`
+  // variant — that suffix exists only to opt the older 4.x models into the
+  // larger window. Pinned so a future entry doesn't invent `claude-opus-5[1m]`.
+  test("5-series entries have no [1m] context variant", () => {
+    for (const { value } of CLAUDE_MODELS) {
+      if (/-5(\[|$)/.test(value)) expect(value).not.toContain("[1m]");
+    }
+  });
+
+  test("tour/guide catalog inherits every review model plus the latest aliases", () => {
+    for (const { value } of CLAUDE_MODELS) {
+      expect(TOUR_CLAUDE_MODELS.some((m) => m.value === value)).toBe(true);
+    }
+    for (const alias of ["sonnet", "opus", "fable"]) {
+      expect(TOUR_CLAUDE_MODELS.some((m) => m.value === alias)).toBe(true);
+    }
+  });
+});
+
 test("uses the canonical GPT-5.6 Sol model ID", () => {
   expect(catalogEntry("gpt-5.6-sol")?.label).toBe("GPT-5.6 Sol");
   expect(CODEX_MODELS.some(({ value }) => value === "gpt-5.6")).toBe(false);
diff --git a/packages/ui/components/AgentsTab.tsx b/packages/ui/components/AgentsTab.tsx
index b0e772f7f..600da1a03 100644
--- a/packages/ui/components/AgentsTab.tsx
+++ b/packages/ui/components/AgentsTab.tsx
@@ -30,6 +30,7 @@ export type { AgentLaunchParams } from '../hooks/useAgentJobs';
 
 export const CLAUDE_MODELS: Array<{ value: string; label: string }> = [
   { value: 'claude-fable-5', label: 'Fable 5' },
+  { value: 'claude-opus-5', label: 'Opus 5' },
   { value: 'claude-opus-4-8', label: 'Opus 4.8' },
   { value: 'claude-opus-4-8[1m]', label: 'Opus 4.8 (1M)' },
   { value: 'claude-sonnet-5', label: 'Sonnet 5' },
diff --git a/packages/ui/hooks/useAgentSettings.ts b/packages/ui/hooks/useAgentSettings.ts
index d29ea6045..dfe0edcdf 100644
--- a/packages/ui/hooks/useAgentSettings.ts
+++ b/packages/ui/hooks/useAgentSettings.ts
@@ -16,7 +16,7 @@ const COOKIE_KEY = 'plannotator.agents';
 // would clobber writes exactly like before.
 const settingsListeners = new Set<(s: AgentSettingsState) => void>();
 
-export const DEFAULT_CLAUDE_MODEL = 'claude-opus-4-7';
+export const DEFAULT_CLAUDE_MODEL = 'claude-opus-5';
 export const DEFAULT_CLAUDE_EFFORT = 'high';
 // gpt-5.3-codex is deprecated (ChatGPT-account Codex rejects it outright) —
 // default to the current flagship everywhere.