Skip to content

Add Claude Fable 5 model #3009

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
juliusmarminge merged 6 commits into from
Jun 9, 2026
+175 −50
Merged

Add Claude Fable 5 model #3009

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
6 commits
Select commit Hold shift + click to select a range
c8cbc04
feat: add Claude Fable 5 model
juliusmarminge Jun 9, 2026
22af73b
Add Claude Fable 5 provider capabilities
juliusmarminge Jun 9, 2026
648538a
test: avoid coupling Claude model presence to capabilities
juliusmarminge Jun 9, 2026
e8d43cb
feat: gate Claude Fable 5 by CLI version
juliusmarminge Jun 9, 2026
9f57633
fix: preserve xhigh effort for Claude Fable 5
juliusmarminge Jun 9, 2026
cbe8a20
Inline Claude effort options for new models
juliusmarminge Jun 9, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
23 changes: 23 additions & 0 deletions apps/server/src/provider/Layers/ClaudeAdapter.test.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -447,6 +447,29 @@ describe("ClaudeAdapterLive", () => {
);
});

it.effect("preserves xhigh effort for Claude Fable 5", () => {
const harness = makeHarness();
return Effect.gen(function* () {
const adapter = yield* ClaudeAdapter;
yield* adapter.startSession({
threadId: THREAD_ID,
provider: ProviderDriverKind.make("claudeAgent"),
modelSelection: createModelSelection(
ProviderInstanceId.make("claudeAgent"),
"claude-fable-5",
[{ id: "effort", value: "xhigh" }],
),
runtimeMode: "full-access",
});

const createInput = harness.getLastCreateQueryInput();
assert.equal(createInput?.options.effort, "xhigh");
}).pipe(
Effect.provideService(Random.Random, makeDeterministicRandomService()),
Effect.provide(harness.layer),
);
});

it.effect("falls back to default effort when unsupported max is requested for Sonnet 4.6", () => {
const harness = makeHarness();
return Effect.gen(function* () {
Expand Down
146 changes: 96 additions & 50 deletions apps/server/src/provider/Layers/ClaudeProvider.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -48,50 +48,42 @@ const CLAUDE_PRESENTATION = {
displayName: "Claude",
showInteractionModeToggle: true,
} as const;
const MINIMUM_CLAUDE_FABLE_5_VERSION = "2.1.169";
const MINIMUM_CLAUDE_OPUS_4_8_VERSION = "2.1.154";
const MINIMUM_CLAUDE_OPUS_4_7_VERSION = "2.1.111";

const CLAUDE_EFFORT_OPTIONS = {
opus48: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High", isDefault: true },
{ value: "xhigh", label: "Extra High" },
{ value: "max", label: "Max" },
{ value: "ultracode", label: "Ultracode" },
{ value: "ultrathink", label: "Ultrathink" },
],
opus47: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High" },
{ value: "xhigh", label: "Extra High", isDefault: true },
{ value: "max", label: "Max" },
{ value: "ultrathink", label: "Ultrathink" },
],
opus46: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High", isDefault: true },
{ value: "max", label: "Max" },
{ value: "ultrathink", label: "Ultrathink" },
],
sonnet46: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High", isDefault: true },
{ value: "max", label: "Max" },
{ value: "ultrathink", label: "Ultrathink" },
],
opus45: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High", isDefault: true },
{ value: "max", label: "Max" },
],
} as const;

const BUILT_IN_MODELS: ReadonlyArray<ServerProviderModel> = [
{
slug: "claude-fable-5",
name: "Claude Fable 5",
isCustom: false,
capabilities: createModelCapabilities({
optionDescriptors: [
buildSelectOptionDescriptor({
id: "effort",
label: "Reasoning",
options: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High", isDefault: true },
{ value: "xhigh", label: "Extra High" },
{ value: "max", label: "Max" },
{ value: "ultracode", label: "Ultracode" },
{ value: "ultrathink", label: "Ultrathink" },
],
promptInjectedValues: ["ultrathink"],
Comment thread
cursor[bot] marked this conversation as resolved.
}),
buildSelectOptionDescriptor({
id: "contextWindow",
label: "Context Window",
options: [
{ value: "200k", label: "200k", isDefault: true },
{ value: "1m", label: "1M" },
],
}),
],
}),
Comment thread
cursor[bot] marked this conversation as resolved.
},
{
slug: "claude-opus-4-8",
name: "Claude Opus 4.8",
Expand All @@ -101,9 +93,21 @@ const BUILT_IN_MODELS: ReadonlyArray<ServerProviderModel> = [
buildSelectOptionDescriptor({
id: "effort",
label: "Reasoning",
options: CLAUDE_EFFORT_OPTIONS.opus48,
options: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High", isDefault: true },
{ value: "xhigh", label: "Extra High" },
{ value: "max", label: "Max" },
{ value: "ultracode", label: "Ultracode" },
{ value: "ultrathink", label: "Ultrathink" },
],
promptInjectedValues: ["ultrathink"],
}),
buildBooleanOptionDescriptor({
id: "fastMode",
label: "Fast Mode",
}),
buildSelectOptionDescriptor({
id: "contextWindow",
label: "Context Window",
Expand All @@ -124,9 +128,20 @@ const BUILT_IN_MODELS: ReadonlyArray<ServerProviderModel> = [
buildSelectOptionDescriptor({
id: "effort",
label: "Reasoning",
options: CLAUDE_EFFORT_OPTIONS.opus47,
options: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High" },
{ value: "xhigh", label: "Extra High", isDefault: true },
{ value: "max", label: "Max" },
{ value: "ultrathink", label: "Ultrathink" },
],
promptInjectedValues: ["ultrathink"],
}),
buildBooleanOptionDescriptor({
id: "fastMode",
label: "Fast Mode",
}),
buildSelectOptionDescriptor({
id: "contextWindow",
label: "Context Window",
Expand All @@ -147,7 +162,13 @@ const BUILT_IN_MODELS: ReadonlyArray<ServerProviderModel> = [
buildSelectOptionDescriptor({
id: "effort",
label: "Reasoning",
options: CLAUDE_EFFORT_OPTIONS.opus46,
options: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High", isDefault: true },
{ value: "max", label: "Max" },
{ value: "ultrathink", label: "Ultrathink" },
],
promptInjectedValues: ["ultrathink"],
}),
buildBooleanOptionDescriptor({
Expand All @@ -174,7 +195,12 @@ const BUILT_IN_MODELS: ReadonlyArray<ServerProviderModel> = [
buildSelectOptionDescriptor({
id: "effort",
label: "Reasoning",
options: CLAUDE_EFFORT_OPTIONS.opus45,
options: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High", isDefault: true },
{ value: "max", label: "Max" },
],
}),
buildBooleanOptionDescriptor({
id: "fastMode",
Expand All @@ -192,7 +218,13 @@ const BUILT_IN_MODELS: ReadonlyArray<ServerProviderModel> = [
buildSelectOptionDescriptor({
id: "effort",
label: "Reasoning",
options: CLAUDE_EFFORT_OPTIONS.sonnet46,
options: [
{ value: "low", label: "Low" },
{ value: "medium", label: "Medium" },
{ value: "high", label: "High", isDefault: true },
{ value: "max", label: "Max" },
{ value: "ultrathink", label: "Ultrathink" },
],
promptInjectedValues: ["ultrathink"],
}),
buildSelectOptionDescriptor({
Expand Down Expand Up @@ -221,6 +253,10 @@ const BUILT_IN_MODELS: ReadonlyArray<ServerProviderModel> = [
},
];

function supportsClaudeFable5(version: string | null | undefined): boolean {
return version ? compareSemverVersions(version, MINIMUM_CLAUDE_FABLE_5_VERSION) >= 0 : false;
}

function supportsClaudeOpus48(version: string | null | undefined): boolean {
return version ? compareSemverVersions(version, MINIMUM_CLAUDE_OPUS_4_8_VERSION) >= 0 : false;
}
Expand All @@ -233,6 +269,9 @@ function getBuiltInClaudeModelsForVersion(
version: string | null | undefined,
): ReadonlyArray<ServerProviderModel> {
return BUILT_IN_MODELS.filter((model) => {
if (model.slug === "claude-fable-5") {
return supportsClaudeFable5(version);
}
if (model.slug === "claude-opus-4-8") {
return supportsClaudeOpus48(version);
}
Expand All @@ -243,6 +282,11 @@ function getBuiltInClaudeModelsForVersion(
});
}

function formatClaudeFable5UpgradeMessage(version: string | null): string {
const versionLabel = version ? `v${version}` : "the installed version";
return `Claude Code ${versionLabel} is too old for Claude Fable 5. Upgrade to v${MINIMUM_CLAUDE_FABLE_5_VERSION} or newer to access it.`;
}

function formatClaudeOpus48UpgradeMessage(version: string | null): string {
const versionLabel = version ? `v${version}` : "the installed version";
return `Claude Code ${versionLabel} is too old for Claude Opus 4.8. Upgrade to v${MINIMUM_CLAUDE_OPUS_4_8_VERSION} or newer to access it.`;
Expand Down Expand Up @@ -294,7 +338,7 @@ export function normalizeClaudeCliEffort(
if (effort === "ultracode") {
return "xhigh";
}
if (effort === "xhigh" && model !== "claude-opus-4-8") {
if (effort === "xhigh" && model !== "claude-fable-5" && model !== "claude-opus-4-8") {
return "max";
}
if (effort === "max" && model === "claude-sonnet-4-6") {
Expand Down Expand Up @@ -688,11 +732,13 @@ export const checkClaudeProviderStatus = Effect.fn("checkClaudeProviderStatus")(
claudeSettings.customModels,
DEFAULT_CLAUDE_MODEL_CAPABILITIES,
);
const versionUpgradeMessage = supportsClaudeOpus48(parsedVersion)
const versionUpgradeMessage = supportsClaudeFable5(parsedVersion)
? undefined
: supportsClaudeOpus47(parsedVersion)
? formatClaudeOpus48UpgradeMessage(parsedVersion)
: formatClaudeOpus47UpgradeMessage(parsedVersion);
: supportsClaudeOpus48(parsedVersion)
? formatClaudeFable5UpgradeMessage(parsedVersion)
: supportsClaudeOpus47(parsedVersion)
? formatClaudeOpus48UpgradeMessage(parsedVersion)
: formatClaudeOpus47UpgradeMessage(parsedVersion);

const capabilities = resolveCapabilities
? yield* resolveCapabilities(claudeSettings).pipe(Effect.orElseSucceed(() => undefined))
Expand Down
56 changes: 56 additions & 0 deletions apps/server/src/provider/Layers/ProviderRegistry.test.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1367,6 +1367,62 @@ it.layer(Layer.mergeAll(NodeServices.layer, ServerSettingsService.layerTest(), T
),
);

it.effect("includes Claude Fable 5 on supported Claude Code versions", () =>
Effect.gen(function* () {
const status = yield* checkClaudeProviderStatus(
defaultClaudeSettings,
claudeCapabilities(),
);
const fable5 = status.models.find((model) => model.slug === "claude-fable-5");
assert.strictEqual(fable5?.name, "Claude Fable 5");
}).pipe(
Effect.provide(
mockSpawnerLayer((args) => {
const joined = args.join(" ");
if (joined === "--version") return { stdout: "2.1.169\n", stderr: "", code: 0 };
if (joined === "auth status")
return {
stdout: '{"loggedIn":true,"authMethod":"claude.ai"}\n',
stderr: "",
code: 0,
};
throw new Error(`Unexpected args: ${joined}`);
}),
),
),
);

it.effect("hides Claude Fable 5 on older Claude Code versions", () =>
Effect.gen(function* () {
const status = yield* checkClaudeProviderStatus(
defaultClaudeSettings,
claudeCapabilities(),
);
assert.strictEqual(
status.models.some((model) => model.slug === "claude-fable-5"),
false,
);
assert.strictEqual(
status.message,
"Claude Code v2.1.168 is too old for Claude Fable 5. Upgrade to v2.1.169 or newer to access it.",
);
}).pipe(
Effect.provide(
mockSpawnerLayer((args) => {
const joined = args.join(" ");
if (joined === "--version") return { stdout: "2.1.168\n", stderr: "", code: 0 };
if (joined === "auth status")
return {
stdout: '{"loggedIn":true,"authMethod":"claude.ai"}\n',
stderr: "",
code: 0,
};
throw new Error(`Unexpected args: ${joined}`);
}),
),
),
);

it.effect(
"includes Claude Opus 4.7 with xhigh as the default effort on supported versions",
() =>
Expand Down
Loading