feat(ai): add max thinking level

packages/agent/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Added
+
+- Added the `max` model thinking level after `xhigh`.
+
 ## [0.80.5] - 2026-07-09
 
 ## [0.80.4] - 2026-07-09

packages/agent/README.md

@@ -164,7 +164,7 @@ const agent = new Agent({
   initialState: {
     systemPrompt: string,
     model: Model<any>,
-    thinkingLevel: "off" | "minimal" | "low" | "medium" | "high" | "xhigh",
+    thinkingLevel: "off" | "minimal" | "low" | "medium" | "high" | "xhigh" | "max",
     tools: AgentTool<any>[],
     messages: AgentMessage[],
   },

packages/agent/src/types.ts

@@ -283,10 +283,10 @@ export interface AgentLoopConfig extends SimpleStreamOptions {
 
 /**
  * Thinking/reasoning level for models that support it.
- * Note: "xhigh" is only supported by selected model families. Use model thinking-level metadata
- * from @earendil-works/pi-ai to detect support for a concrete model.
+ * Note: "xhigh" and "max" are only supported by selected model families. Use model
+ * thinking-level metadata from @earendil-works/pi-ai to detect support for a concrete model.
  */
-export type ThinkingLevel = "off" | "minimal" | "low" | "medium" | "high" | "xhigh";
+export type ThinkingLevel = "off" | "minimal" | "low" | "medium" | "high" | "xhigh" | "max";
 
 /**
  * Extensible interface for custom app messages.

packages/ai/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Added
+
+- Added a separate opt-in `max` thinking level, including native `xhigh` and `max` support for GPT-5.6 and Anthropic adaptive-thinking effort metadata matching Anthropic's documentation: `max` on all adaptive Claude models, native `xhigh` on Opus 4.7/4.8, Sonnet 5, and Fable 5 only.
+
 ### Fixed
 
 - Fixed post-compaction output-token budgeting to ignore stale assistant usage from before the compaction boundary ([#6464](https://github.com/earendil-works/pi/issues/6464)).

packages/ai/README.md

@@ -730,7 +730,7 @@ if (model.reasoning) {
 const response = await models.completeSimple(model, {
   messages: [{ role: 'user', content: 'Solve: 2x + 5 = 13', timestamp: Date.now() }]
 }, {
-  reasoning: 'medium'  // 'minimal' | 'low' | 'medium' | 'high' | 'xhigh'
+  reasoning: 'medium'  // 'minimal' | 'low' | 'medium' | 'high' | 'xhigh' | 'max'
 });
 
 // Access thinking and text blocks
@@ -743,6 +743,8 @@ for (const block of response.content) {
 }
 ```
 
+`xhigh` and `max` are model-specific, opt-in levels. Use `getSupportedThinkingLevels(model)` to determine whether a concrete model exposes either level; models such as GPT-5.6 can expose both.
+
 ### Provider-Specific Options (stream/complete)
 
 `models.stream()`/`complete()` accept the owning API's full option set. Use `hasApi()` to narrow a dynamically looked-up model to its API for full option typing:
@@ -999,7 +1001,7 @@ Custom models can carry `headers` (e.g. proxies behind bot detection) and `compa
 
 Some OpenAI-compatible servers do not understand the `developer` role used for reasoning-capable models. For those providers, set `compat.supportsDeveloperRole` to `false` so the system prompt is sent as a `system` message instead. If the server also does not support `reasoning_effort`, set `compat.supportsReasoningEffort` to `false` too. This commonly applies to Ollama, vLLM, SGLang, and similar OpenAI-compatible servers.
 
-Use model-level `thinkingLevelMap` to describe model-specific thinking controls. Keys are pi thinking levels (`off`, `minimal`, `low`, `medium`, `high`, `xhigh`). Missing keys use provider defaults, string values are sent to the provider, and `null` marks a level unsupported.
+Use model-level `thinkingLevelMap` to describe model-specific thinking controls. Keys are pi thinking levels (`off`, `minimal`, `low`, `medium`, `high`, `xhigh`, `max`). Missing standard levels through `high` use provider defaults; `xhigh` and `max` are opt-in and require a non-null map entry. String values are sent to the provider, `null` marks a level unsupported, and maps may skip levels.
 
 ```typescript
 const ollamaReasoningModel: Model<'openai-completions'> = {

packages/ai/scripts/generate-models.ts

@@ -160,7 +160,7 @@ const ZAI_GLM52_THINKING_LEVEL_MAP = {
 	low: "high",
 	medium: "high",
 	high: "high",
-	xhigh: "max",
+	max: "max",
 } as const;
 const OPENCODE_GO_GLM52_THINKING_LEVEL_MAP = {
 	off: null,
@@ -168,7 +168,7 @@ const OPENCODE_GO_GLM52_THINKING_LEVEL_MAP = {
 	low: null,
 	medium: null,
 	high: "high",
-	xhigh: "max",
+	max: "max",
 } as const;
 const EAGER_TOOL_INPUT_STREAMING_UNSUPPORTED_ANTHROPIC_MODELS = new Set([
 	"github-copilot:claude-haiku-4.5",
@@ -181,7 +181,7 @@ const DEEPSEEK_V4_THINKING_LEVEL_MAP = {
 	low: null,
 	medium: null,
 	high: "high",
-	xhigh: "max",
+	max: "max",
 } as const;
 
 const ANT_LING_RING_THINKING_LEVEL_MAP = {
@@ -235,7 +235,7 @@ const GITHUB_COPILOT_EXTENDED_CONTEXT_MODELS = new Set([
 const GITHUB_COPILOT_THINKING_LEVEL_OVERRIDES = {
 	"claude-opus-4.7": { minimal: "low" },
 	"claude-opus-4.8": { minimal: "low" },
-	"claude-sonnet-4.6": { minimal: "low", xhigh: "max" },
+	"claude-sonnet-4.6": { minimal: "low", max: "max" },
 } satisfies Record<string, NonNullable<Model<Api>["thinkingLevelMap"]>>;
 
 function mergeThinkingLevelMap(model: Model<any>, map: NonNullable<Model<any>["thinkingLevelMap"]>): void {
@@ -271,6 +271,16 @@ function supportsOpenAiXhigh(modelId: string): boolean {
 	);
 }
 
+function supportsOpenAiMax(model: Model<Api>): boolean {
+	return (
+		model.id.includes("gpt-5.6") &&
+		(model.api === "openai-responses" ||
+			model.api === "azure-openai-responses" ||
+			model.api === "openai-codex-responses" ||
+			model.api === "openai-completions")
+	);
+}
+
 function isGoogleThinkingApi(model: Model<any>): boolean {
 	return model.api === "google-generative-ai" || model.api === "google-vertex";
 }
@@ -472,28 +482,41 @@ function applyThinkingLevelMetadata(model: Model<any>): void {
 	if (supportsOpenAiXhigh(model.id)) {
 		mergeThinkingLevelMap(model, { xhigh: "xhigh" });
 	}
+	if (supportsOpenAiMax(model)) {
+		mergeThinkingLevelMap(model, { max: "max" });
+	}
 	if (model.provider === "openai" && model.id === "gpt-5.5") {
 		mergeThinkingLevelMap(model, { minimal: null });
 	}
 	if (model.id.endsWith("gpt-5.5-pro")) {
 		mergeThinkingLevelMap(model, { off: null, minimal: null, low: null });
 	}
-	if (model.id.includes("opus-4-6") || model.id.includes("opus-4.6")) {
-		mergeThinkingLevelMap(model, { xhigh: "max" });
+	// Anthropic adaptive-thinking effort support (per Anthropic adaptive thinking docs):
+	// - "max" is available on all adaptive-thinking Claude models.
+	// - "xhigh" is only available on Opus 4.7/4.8, Sonnet 5, and Fable 5.
+	if (
+		model.id.includes("opus-4-6") ||
+		model.id.includes("opus-4.6") ||
+		model.id.includes("sonnet-4-6") ||
+		model.id.includes("sonnet-4.6")
+	) {
+		mergeThinkingLevelMap(model, { max: "max" });
 	}
 	if (
 		model.id.includes("opus-4-7") ||
 		model.id.includes("opus-4.7") ||
 		model.id.includes("opus-4-8") ||
-		model.id.includes("opus-4.8")
+		model.id.includes("opus-4.8") ||
+		model.id.includes("sonnet-5") ||
+		model.id.includes("sonnet.5")
 	) {
-		mergeThinkingLevelMap(model, { xhigh: "xhigh" });
+		mergeThinkingLevelMap(model, { xhigh: "xhigh", max: "max" });
 	}
 	if (
 		(model.api === "anthropic-messages" || model.api === "bedrock-converse-stream") &&
 		model.id.includes("fable-5")
 	) {
-		mergeThinkingLevelMap(model, { off: null, xhigh: "xhigh" });
+		mergeThinkingLevelMap(model, { off: null, xhigh: "xhigh", max: "max" });
 	}
 	if (model.api === "anthropic-messages" && isAnthropicAdaptiveThinkingModel(model.id)) {
 		mergeAnthropicMessagesCompat(model, { forceAdaptiveThinking: true });
@@ -505,7 +528,7 @@ function applyThinkingLevelMetadata(model: Model<any>): void {
 		mergeThinkingLevelMap(
 			model,
 			model.provider === "openrouter"
-				? { ...DEEPSEEK_V4_THINKING_LEVEL_MAP, xhigh: "xhigh" }
+				? { ...DEEPSEEK_V4_THINKING_LEVEL_MAP, xhigh: "xhigh", max: null }
 				: DEEPSEEK_V4_THINKING_LEVEL_MAP,
 		);
 	}
@@ -544,7 +567,7 @@ function applyThinkingLevelMetadata(model: Model<any>): void {
 		mergeThinkingLevelMap(model, { xhigh: "xhigh" });
 	}
 	if (model.provider === "fireworks" && model.id.includes("glm-5p2")) {
-		mergeThinkingLevelMap(model, { off: "none", minimal: null, low: "high", medium: "high", xhigh: "max" });
+		mergeThinkingLevelMap(model, { off: "none", minimal: null, low: "high", medium: "high", max: "max" });
 	}
 	if (model.provider === "opencode-go" && model.id === "glm-5.2") {
 		mergeThinkingLevelMap(model, OPENCODE_GO_GLM52_THINKING_LEVEL_MAP);

packages/ai/src/api/anthropic-messages.ts

@@ -742,7 +742,8 @@ export const stream: StreamFunction<"anthropic-messages", AnthropicOptions> = (
 
 /**
  * Map ThinkingLevel to Anthropic effort levels for adaptive thinking.
- * Note: effort "max" is only valid on Opus 4.6, while Opus 4.7+ and Fable 5 support "xhigh".
+ * Note: effort "max" is available on all adaptive-thinking Claude models, while native
+ * "xhigh" is only available on Opus 4.7/4.8, Sonnet 5, and Fable 5.
  */
 function mapThinkingLevelToEffort(
 	model: Model<"anthropic-messages">,

packages/ai/src/api/azure-openai-responses.ts

@@ -52,7 +52,7 @@ function formatAzureOpenAIError(error: unknown): string {
 
 // Azure OpenAI Responses-specific options
 export interface AzureOpenAIResponsesOptions extends StreamOptions {
-	reasoningEffort?: "minimal" | "low" | "medium" | "high" | "xhigh";
+	reasoningEffort?: "minimal" | "low" | "medium" | "high" | "xhigh" | "max";
 	reasoningSummary?: "auto" | "detailed" | "concise" | null;
 	azureApiVersion?: string;
 	azureResourceName?: string;

packages/ai/src/api/bedrock-converse-stream.ts

@@ -582,7 +582,9 @@ function supportsAdaptiveThinking(modelId: string, modelName?: string): boolean
 
 function supportsNativeXhighEffort(model: Model<"bedrock-converse-stream">): boolean {
 	const candidates = getModelMatchCandidates(model.id, model.name);
-	return candidates.some((s) => s.includes("opus-4-7") || s.includes("opus-4-8") || s.includes("fable-5"));
+	return candidates.some(
+		(s) => s.includes("opus-4-7") || s.includes("opus-4-8") || s.includes("sonnet-5") || s.includes("fable-5"),
+	);
 }
 
 function mapThinkingLevelToEffort(
@@ -1025,11 +1027,12 @@ function buildAdditionalModelRequestFields(
 						low: 2048,
 						medium: 8192,
 						high: 16384,
-						xhigh: 16384, // Claude doesn't support xhigh, clamp to high
+						xhigh: 16384, // Budget-based Claude clamps extended levels to high
+						max: 16384,
 					};
 
-					// Custom budgets override defaults (xhigh not in ThinkingBudgets, use high)
-					const level = options.reasoning === "xhigh" ? "high" : options.reasoning;
+					// Custom budgets only cover token-based levels through high.
+					const level = options.reasoning === "xhigh" || options.reasoning === "max" ? "high" : options.reasoning;
 					const budget = options.thinkingBudgets?.[level] ?? defaultBudgets[options.reasoning];
 
 					return {

packages/ai/src/api/google-generative-ai.ts

@@ -400,7 +400,7 @@ function buildParams(
 	return params;
 }
 
-type ClampedThinkingLevel = Exclude<ThinkingLevel, "xhigh">;
+type ClampedThinkingLevel = Exclude<ThinkingLevel, "xhigh" | "max">;
 
 function isGemma4Model(model: Model<"google-generative-ai">): boolean {
 	return /gemma-?4/.test(model.id.toLowerCase());

packages/ai/src/api/google-vertex.ts

@@ -498,7 +498,7 @@ function buildParams(
 	return params;
 }
 
-type ClampedThinkingLevel = Exclude<PiThinkingLevel, "xhigh">;
+type ClampedThinkingLevel = Exclude<PiThinkingLevel, "xhigh" | "max">;
 
 function isGemini3ProModel(model: Model<"google-generative-ai">): boolean {
 	return /gemini-3(?:\.\d+)?-pro/.test(model.id.toLowerCase());

packages/ai/src/api/openai-codex-responses.ts

@@ -80,7 +80,7 @@ const CODEX_RESPONSE_STATUSES = new Set<CodexResponseStatus>([
 // ============================================================================
 
 export interface OpenAICodexResponsesOptions extends StreamOptions {
-	reasoningEffort?: "none" | "minimal" | "low" | "medium" | "high" | "xhigh";
+	reasoningEffort?: "none" | "minimal" | "low" | "medium" | "high" | "xhigh" | "max";
 	reasoningSummary?: "auto" | "concise" | "detailed" | "off" | "on" | null;
 	serviceTier?: ResponseCreateParamsStreaming["service_tier"];
 	textVerbosity?: "low" | "medium" | "high";

packages/ai/src/api/openai-completions.ts

@@ -109,7 +109,7 @@ function isEncryptedReasoningDetail(detail: unknown): detail is OpenAIEncryptedR
 
 export interface OpenAICompletionsOptions extends StreamOptions {
 	toolChoice?: "auto" | "none" | "required" | { type: "function"; function: { name: string } };
-	reasoningEffort?: "minimal" | "low" | "medium" | "high" | "xhigh";
+	reasoningEffort?: "minimal" | "low" | "medium" | "high" | "xhigh" | "max";
 }
 
 interface OpenAICompatCacheControl {

packages/ai/src/api/openai-responses.ts

@@ -78,7 +78,7 @@ function formatOpenAIResponsesError(error: unknown): string {
 
 // OpenAI Responses-specific options
 export interface OpenAIResponsesOptions extends StreamOptions {
-	reasoningEffort?: "minimal" | "low" | "medium" | "high" | "xhigh";
+	reasoningEffort?: "minimal" | "low" | "medium" | "high" | "xhigh" | "max";
 	reasoningSummary?: "auto" | "detailed" | "concise" | null;
 	serviceTier?: ResponseCreateParamsStreaming["service_tier"];
 }

packages/ai/src/api/simple-options.ts

@@ -44,8 +44,8 @@ export function buildBaseOptions(
 	};
 }
 
-export function clampReasoning(effort: ThinkingLevel | undefined): Exclude<ThinkingLevel, "xhigh"> | undefined {
-	return effort === "xhigh" ? "high" : effort;
+export function clampReasoning(effort: ThinkingLevel | undefined): Exclude<ThinkingLevel, "xhigh" | "max"> | undefined {
+	return effort === "xhigh" || effort === "max" ? "high" : effort;
 }
 
 export function adjustMaxTokensForThinking(

packages/ai/src/models.ts

@@ -394,7 +394,7 @@ export function calculateCost<TApi extends Api>(model: Model<TApi>, usage: Usage
 	return usage.cost;
 }
 
-const EXTENDED_THINKING_LEVELS: ModelThinkingLevel[] = ["off", "minimal", "low", "medium", "high", "xhigh"];
+const EXTENDED_THINKING_LEVELS: ModelThinkingLevel[] = ["off", "minimal", "low", "medium", "high", "xhigh", "max"];
 
 export function getSupportedThinkingLevels<TApi extends Api>(model: Model<TApi>): ModelThinkingLevel[] {
 	if (!model.reasoning) return ["off"];
@@ -402,7 +402,7 @@ export function getSupportedThinkingLevels<TApi extends Api>(model: Model<TApi>)
 	return EXTENDED_THINKING_LEVELS.filter((level) => {
 		const mapped = model.thinkingLevelMap?.[level];
 		if (mapped === null) return false;
-		if (level === "xhigh") return mapped !== undefined;
+		if (level === "xhigh" || level === "max") return mapped !== undefined;
 		return true;
 	});
 }

packages/ai/src/providers/amazon-bedrock.models.ts

@@ -79,7 +79,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 10,
@@ -148,7 +148,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -166,7 +166,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -184,7 +184,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -219,6 +219,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3,
@@ -236,6 +237,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,
@@ -270,7 +272,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 16.5,
@@ -288,7 +290,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -323,6 +325,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3.3,
@@ -340,6 +343,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,
@@ -408,7 +412,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.eu-central-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 11,
@@ -460,7 +464,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.eu-central-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5.5,
@@ -478,7 +482,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.eu-central-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5.5,
@@ -496,7 +500,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.eu-central-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5.5,
@@ -531,6 +535,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.eu-central-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3.3,
@@ -548,6 +553,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.eu-central-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2.2,
@@ -565,7 +571,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 10,
@@ -617,7 +623,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -635,7 +641,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -653,7 +659,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -688,6 +694,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3,
@@ -705,6 +712,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,
@@ -773,7 +781,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -791,7 +799,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -826,6 +834,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3,
@@ -843,6 +852,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,
@@ -1508,7 +1518,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 10,
@@ -1577,7 +1587,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -1595,7 +1605,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -1613,7 +1623,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -1648,6 +1658,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3,
@@ -1665,6 +1676,7 @@ export const AMAZON_BEDROCK_MODELS = {
 		provider: "amazon-bedrock",
 		baseUrl: "https://bedrock-runtime.us-east-1.amazonaws.com",
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,

packages/ai/src/providers/anthropic.models.ts

@@ -12,7 +12,7 @@ export const ANTHROPIC_MODELS = {
 		baseUrl: "https://api.anthropic.com",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 10,
@@ -133,7 +133,7 @@ export const ANTHROPIC_MODELS = {
 		baseUrl: "https://api.anthropic.com",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -152,7 +152,7 @@ export const ANTHROPIC_MODELS = {
 		baseUrl: "https://api.anthropic.com",
 		compat: {"forceAdaptiveThinking":true,"supportsTemperature":false},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -171,7 +171,7 @@ export const ANTHROPIC_MODELS = {
 		baseUrl: "https://api.anthropic.com",
 		compat: {"forceAdaptiveThinking":true,"supportsTemperature":false},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -224,6 +224,7 @@ export const ANTHROPIC_MODELS = {
 		baseUrl: "https://api.anthropic.com",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3,
@@ -242,6 +243,7 @@ export const ANTHROPIC_MODELS = {
 		baseUrl: "https://api.anthropic.com",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,

packages/ai/src/providers/azure-openai-responses.models.ts

@@ -613,7 +613,7 @@ export const AZURE_OPENAI_RESPONSES_MODELS = {
 		provider: "azure-openai-responses",
 		baseUrl: "",
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -631,7 +631,7 @@ export const AZURE_OPENAI_RESPONSES_MODELS = {
 		provider: "azure-openai-responses",
 		baseUrl: "",
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 1,
@@ -649,7 +649,7 @@ export const AZURE_OPENAI_RESPONSES_MODELS = {
 		provider: "azure-openai-responses",
 		baseUrl: "",
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -667,7 +667,7 @@ export const AZURE_OPENAI_RESPONSES_MODELS = {
 		provider: "azure-openai-responses",
 		baseUrl: "",
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2.5,

packages/ai/src/providers/cloudflare-ai-gateway.models.ts

@@ -120,7 +120,7 @@ export const CLOUDFLARE_AI_GATEWAY_MODELS = {
 		baseUrl: "https://gateway.ai.cloudflare.com/v1/{CLOUDFLARE_ACCOUNT_ID}/{CLOUDFLARE_GATEWAY_ID}/anthropic",
 		compat: {"sendSessionAffinityHeaders":true,"forceAdaptiveThinking":true},
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 10,
@@ -211,7 +211,7 @@ export const CLOUDFLARE_AI_GATEWAY_MODELS = {
 		baseUrl: "https://gateway.ai.cloudflare.com/v1/{CLOUDFLARE_ACCOUNT_ID}/{CLOUDFLARE_GATEWAY_ID}/anthropic",
 		compat: {"sendSessionAffinityHeaders":true,"forceAdaptiveThinking":true},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -230,7 +230,7 @@ export const CLOUDFLARE_AI_GATEWAY_MODELS = {
 		baseUrl: "https://gateway.ai.cloudflare.com/v1/{CLOUDFLARE_ACCOUNT_ID}/{CLOUDFLARE_GATEWAY_ID}/anthropic",
 		compat: {"sendSessionAffinityHeaders":true,"forceAdaptiveThinking":true,"supportsTemperature":false},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -249,7 +249,7 @@ export const CLOUDFLARE_AI_GATEWAY_MODELS = {
 		baseUrl: "https://gateway.ai.cloudflare.com/v1/{CLOUDFLARE_ACCOUNT_ID}/{CLOUDFLARE_GATEWAY_ID}/anthropic",
 		compat: {"sendSessionAffinityHeaders":true,"forceAdaptiveThinking":true,"supportsTemperature":false},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -304,6 +304,7 @@ export const CLOUDFLARE_AI_GATEWAY_MODELS = {
 		baseUrl: "https://gateway.ai.cloudflare.com/v1/{CLOUDFLARE_ACCOUNT_ID}/{CLOUDFLARE_GATEWAY_ID}/anthropic",
 		compat: {"sendSessionAffinityHeaders":true,"forceAdaptiveThinking":true},
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3,
@@ -322,6 +323,7 @@ export const CLOUDFLARE_AI_GATEWAY_MODELS = {
 		baseUrl: "https://gateway.ai.cloudflare.com/v1/{CLOUDFLARE_ACCOUNT_ID}/{CLOUDFLARE_GATEWAY_ID}/anthropic",
 		compat: {"sendSessionAffinityHeaders":true,"forceAdaptiveThinking":true},
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,

packages/ai/src/providers/deepseek.models.ts

@@ -12,7 +12,7 @@ export const DEEPSEEK_MODELS = {
 		baseUrl: "https://api.deepseek.com",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false,"requiresReasoningContentOnAssistantMessages":true,"thinkingFormat":"deepseek"},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"max"},
+		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 0.14,
@@ -31,7 +31,7 @@ export const DEEPSEEK_MODELS = {
 		baseUrl: "https://api.deepseek.com",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false,"requiresReasoningContentOnAssistantMessages":true,"thinkingFormat":"deepseek"},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"max"},
+		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 0.435,

packages/ai/src/providers/fireworks.models.ts

@@ -66,7 +66,7 @@ export const FIREWORKS_MODELS = {
 		baseUrl: "https://api.fireworks.ai/inference/v1",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false},
 		reasoning: true,
-		thinkingLevelMap: {"off":"none","minimal":null,"low":"high","medium":"high","xhigh":"max"},
+		thinkingLevelMap: {"off":"none","minimal":null,"low":"high","medium":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 1.4,
@@ -229,7 +229,7 @@ export const FIREWORKS_MODELS = {
 		baseUrl: "https://api.fireworks.ai/inference/v1",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false},
 		reasoning: true,
-		thinkingLevelMap: {"off":"none","minimal":null,"low":"high","medium":"high","xhigh":"max"},
+		thinkingLevelMap: {"off":"none","minimal":null,"low":"high","medium":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 2.1,

packages/ai/src/providers/github-copilot.models.ts

@@ -69,7 +69,7 @@ export const GITHUB_COPILOT_MODELS = {
 		headers: {"User-Agent":"GitHubCopilotChat/0.35.0","Editor-Version":"vscode/1.107.0","Editor-Plugin-Version":"copilot-chat/0.35.0","Copilot-Integration-Id":"vscode-chat"},
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -89,7 +89,7 @@ export const GITHUB_COPILOT_MODELS = {
 		headers: {"User-Agent":"GitHubCopilotChat/0.35.0","Editor-Version":"vscode/1.107.0","Editor-Plugin-Version":"copilot-chat/0.35.0","Copilot-Integration-Id":"vscode-chat"},
 		compat: {"forceAdaptiveThinking":true,"supportsTemperature":false},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh","minimal":"low"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max","minimal":"low"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -109,7 +109,7 @@ export const GITHUB_COPILOT_MODELS = {
 		headers: {"User-Agent":"GitHubCopilotChat/0.35.0","Editor-Version":"vscode/1.107.0","Editor-Plugin-Version":"copilot-chat/0.35.0","Copilot-Integration-Id":"vscode-chat"},
 		compat: {"forceAdaptiveThinking":true,"supportsTemperature":false},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh","minimal":"low"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max","minimal":"low"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -167,7 +167,7 @@ export const GITHUB_COPILOT_MODELS = {
 		headers: {"User-Agent":"GitHubCopilotChat/0.35.0","Editor-Version":"vscode/1.107.0","Editor-Plugin-Version":"copilot-chat/0.35.0","Copilot-Integration-Id":"vscode-chat"},
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":"low","xhigh":"max"},
+		thinkingLevelMap: {"max":"max","minimal":"low"},
 		input: ["text", "image"],
 		cost: {
 			input: 3,
@@ -187,6 +187,7 @@ export const GITHUB_COPILOT_MODELS = {
 		headers: {"User-Agent":"GitHubCopilotChat/0.35.0","Editor-Version":"vscode/1.107.0","Editor-Plugin-Version":"copilot-chat/0.35.0","Copilot-Integration-Id":"vscode-chat"},
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,

packages/ai/src/providers/openai-codex.models.ts

@@ -83,7 +83,7 @@ export const OPENAI_CODEX_MODELS = {
 		provider: "openai-codex",
 		baseUrl: "https://chatgpt.com/backend-api",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh","minimal":"low"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max","minimal":"low"},
 		input: ["text", "image"],
 		cost: {
 			input: 1,
@@ -101,7 +101,7 @@ export const OPENAI_CODEX_MODELS = {
 		provider: "openai-codex",
 		baseUrl: "https://chatgpt.com/backend-api",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh","minimal":"low"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max","minimal":"low"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -119,7 +119,7 @@ export const OPENAI_CODEX_MODELS = {
 		provider: "openai-codex",
 		baseUrl: "https://chatgpt.com/backend-api",
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh","minimal":"low"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max","minimal":"low"},
 		input: ["text", "image"],
 		cost: {
 			input: 2.5,

packages/ai/src/providers/openai.models.ts

@@ -613,7 +613,7 @@ export const OPENAI_MODELS = {
 		provider: "openai",
 		baseUrl: "https://api.openai.com/v1",
 		reasoning: true,
-		thinkingLevelMap: {"off":"none","xhigh":"xhigh"},
+		thinkingLevelMap: {"off":"none","xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -631,7 +631,7 @@ export const OPENAI_MODELS = {
 		provider: "openai",
 		baseUrl: "https://api.openai.com/v1",
 		reasoning: true,
-		thinkingLevelMap: {"off":"none","xhigh":"xhigh"},
+		thinkingLevelMap: {"off":"none","xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 1,
@@ -649,7 +649,7 @@ export const OPENAI_MODELS = {
 		provider: "openai",
 		baseUrl: "https://api.openai.com/v1",
 		reasoning: true,
-		thinkingLevelMap: {"off":"none","xhigh":"xhigh"},
+		thinkingLevelMap: {"off":"none","xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -667,7 +667,7 @@ export const OPENAI_MODELS = {
 		provider: "openai",
 		baseUrl: "https://api.openai.com/v1",
 		reasoning: true,
-		thinkingLevelMap: {"off":"none","xhigh":"xhigh"},
+		thinkingLevelMap: {"off":"none","xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2.5,

packages/ai/src/providers/opencode-go.models.ts

@@ -12,7 +12,7 @@ export const OPENCODE_GO_MODELS = {
 		baseUrl: "https://opencode.ai/zen/go/v1",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false,"maxTokensField":"max_tokens","requiresReasoningContentOnAssistantMessages":true,"thinkingFormat":"deepseek"},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"max"},
+		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 0.14,
@@ -31,7 +31,7 @@ export const OPENCODE_GO_MODELS = {
 		baseUrl: "https://opencode.ai/zen/go/v1",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false,"maxTokensField":"max_tokens","requiresReasoningContentOnAssistantMessages":true,"thinkingFormat":"deepseek"},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"max"},
+		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 1.74,
@@ -68,7 +68,7 @@ export const OPENCODE_GO_MODELS = {
 		baseUrl: "https://opencode.ai/zen/go/v1",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false,"maxTokensField":"max_tokens"},
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"max"},
+		thinkingLevelMap: {"off":null,"minimal":null,"low":null,"medium":null,"high":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 1.4,

packages/ai/src/providers/opencode.models.ts

@@ -30,7 +30,7 @@ export const OPENCODE_MODELS = {
 		baseUrl: "https://opencode.ai/zen",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 10,
@@ -100,7 +100,7 @@ export const OPENCODE_MODELS = {
 		baseUrl: "https://opencode.ai/zen",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -119,7 +119,7 @@ export const OPENCODE_MODELS = {
 		baseUrl: "https://opencode.ai/zen",
 		compat: {"forceAdaptiveThinking":true,"supportsTemperature":false},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -138,7 +138,7 @@ export const OPENCODE_MODELS = {
 		baseUrl: "https://opencode.ai/zen",
 		compat: {"forceAdaptiveThinking":true,"supportsTemperature":false},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -191,6 +191,7 @@ export const OPENCODE_MODELS = {
 		baseUrl: "https://opencode.ai/zen",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3,
@@ -209,6 +210,7 @@ export const OPENCODE_MODELS = {
 		baseUrl: "https://opencode.ai/zen",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,
@@ -227,7 +229,7 @@ export const OPENCODE_MODELS = {
 		baseUrl: "https://opencode.ai/zen/v1",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false,"maxTokensField":"max_tokens","supportsLongCacheRetention":false,"requiresReasoningContentOnAssistantMessages":true},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"max"},
+		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 0.14,
@@ -246,7 +248,7 @@ export const OPENCODE_MODELS = {
 		baseUrl: "https://opencode.ai/zen/v1",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false,"maxTokensField":"max_tokens","requiresReasoningContentOnAssistantMessages":true},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"max"},
+		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 0,
@@ -265,7 +267,7 @@ export const OPENCODE_MODELS = {
 		baseUrl: "https://opencode.ai/zen/v1",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false,"maxTokensField":"max_tokens","supportsLongCacheRetention":false,"requiresReasoningContentOnAssistantMessages":true},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"max"},
+		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 1.74,

packages/ai/src/providers/openrouter.models.ts

@@ -282,7 +282,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter","cacheControlFormat":"anthropic"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -301,7 +301,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter","cacheControlFormat":"anthropic"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -320,7 +320,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter","cacheControlFormat":"anthropic"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 30,
@@ -339,7 +339,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter","cacheControlFormat":"anthropic"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -358,7 +358,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter","cacheControlFormat":"anthropic"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 10,
@@ -413,6 +413,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter","cacheControlFormat":"anthropic"},
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3,
@@ -431,6 +432,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter","cacheControlFormat":"anthropic"},
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,
@@ -791,7 +793,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"supportsDeveloperRole":false,"thinkingFormat":"openrouter","requiresReasoningContentOnAssistantMessages":true},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"xhigh"},
+		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","max":null,"xhigh":"xhigh"},
 		input: ["text"],
 		cost: {
 			input: 0.09,
@@ -810,7 +812,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"supportsDeveloperRole":false,"thinkingFormat":"openrouter","requiresReasoningContentOnAssistantMessages":true},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","xhigh":"xhigh"},
+		thinkingLevelMap: {"minimal":null,"low":null,"medium":null,"high":"high","max":null,"xhigh":"xhigh"},
 		input: ["text"],
 		cost: {
 			input: 0.435,
@@ -1486,7 +1488,7 @@ export const OPENROUTER_MODELS = {
 			cacheWrite: 0,
 		},
 		contextWindow: 1048576,
-		maxTokens: 512000,
+		maxTokens: 131072,
 	} satisfies Model<"openai-completions">,
 	"mistralai/codestral-2508": {
 		id: "mistralai/codestral-2508",
@@ -2804,7 +2806,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 1,
@@ -2823,7 +2825,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 1,
@@ -2842,7 +2844,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -2861,7 +2863,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -2880,7 +2882,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2.5,
@@ -2899,7 +2901,7 @@ export const OPENROUTER_MODELS = {
 		baseUrl: "https://openrouter.ai/api/v1",
 		compat: {"thinkingFormat":"openrouter"},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2.5,

packages/ai/src/providers/vercel-ai-gateway.models.ts

@@ -522,7 +522,7 @@ export const VERCEL_AI_GATEWAY_MODELS = {
 		baseUrl: "https://ai-gateway.vercel.sh",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
-		thinkingLevelMap: {"off":null,"xhigh":"xhigh"},
+		thinkingLevelMap: {"off":null,"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 10,
@@ -609,7 +609,7 @@ export const VERCEL_AI_GATEWAY_MODELS = {
 		baseUrl: "https://ai-gateway.vercel.sh",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"max"},
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -628,7 +628,7 @@ export const VERCEL_AI_GATEWAY_MODELS = {
 		baseUrl: "https://ai-gateway.vercel.sh",
 		compat: {"forceAdaptiveThinking":true,"supportsTemperature":false},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -647,7 +647,7 @@ export const VERCEL_AI_GATEWAY_MODELS = {
 		baseUrl: "https://ai-gateway.vercel.sh",
 		compat: {"forceAdaptiveThinking":true,"supportsTemperature":false},
 		reasoning: true,
-		thinkingLevelMap: {"xhigh":"xhigh"},
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 5,
@@ -700,6 +700,7 @@ export const VERCEL_AI_GATEWAY_MODELS = {
 		baseUrl: "https://ai-gateway.vercel.sh",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
+		thinkingLevelMap: {"max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 3,
@@ -718,6 +719,7 @@ export const VERCEL_AI_GATEWAY_MODELS = {
 		baseUrl: "https://ai-gateway.vercel.sh",
 		compat: {"forceAdaptiveThinking":true},
 		reasoning: true,
+		thinkingLevelMap: {"xhigh":"xhigh","max":"max"},
 		input: ["text", "image"],
 		cost: {
 			input: 2,

packages/ai/src/providers/zai-coding-cn.models.ts

@@ -84,7 +84,7 @@ export const ZAI_CODING_CN_MODELS = {
 		baseUrl: "https://open.bigmodel.cn/api/coding/paas/v4",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false,"supportsReasoningEffort":true,"thinkingFormat":"zai","zaiToolStream":true},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":"high","medium":"high","high":"high","xhigh":"max"},
+		thinkingLevelMap: {"minimal":null,"low":"high","medium":"high","high":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 0,

packages/ai/src/providers/zai.models.ts

@@ -84,7 +84,7 @@ export const ZAI_MODELS = {
 		baseUrl: "https://api.z.ai/api/coding/paas/v4",
 		compat: {"supportsStore":false,"supportsDeveloperRole":false,"supportsReasoningEffort":true,"thinkingFormat":"zai","zaiToolStream":true},
 		reasoning: true,
-		thinkingLevelMap: {"minimal":null,"low":"high","medium":"high","high":"high","xhigh":"max"},
+		thinkingLevelMap: {"minimal":null,"low":"high","medium":"high","high":"high","max":"max"},
 		input: ["text"],
 		cost: {
 			input: 0,

packages/ai/src/types.ts

@@ -71,7 +71,7 @@ export type KnownImagesProvider = "openrouter";
 
 export type ImagesProviderId = KnownImagesProvider | string;
 
-export type ThinkingLevel = "minimal" | "low" | "medium" | "high" | "xhigh";
+export type ThinkingLevel = "minimal" | "low" | "medium" | "high" | "xhigh" | "max";
 export type ModelThinkingLevel = "off" | ThinkingLevel;
 export type ThinkingLevelMap = Partial<Record<ModelThinkingLevel, string | null>>;
 export type ChatTemplateKwargValue =

packages/ai/test/codex-websocket-cached-probe.ts

@@ -19,7 +19,7 @@ import {
 import { getModel } from "../src/compat.ts";
 import type { AssistantMessage, Context, Message, Model, Tool, ToolResultMessage, Transport } from "../src/types.ts";
 
-type ThinkingLevel = "minimal" | "low" | "medium" | "high" | "xhigh";
+type ThinkingLevel = "minimal" | "low" | "medium" | "high" | "xhigh" | "max";
 
 interface Args {
 	turns: number;
@@ -58,7 +58,14 @@ function parseArgs(argv: string[]): Args {
 				break;
 			case "--reasoning": {
 				const value = required(argv[++i], arg);
-				if (value !== "minimal" && value !== "low" && value !== "medium" && value !== "high" && value !== "xhigh") {
+				if (
+					value !== "minimal" &&
+					value !== "low" &&
+					value !== "medium" &&
+					value !== "high" &&
+					value !== "xhigh" &&
+					value !== "max"
+				) {
 					throw new Error(`Invalid --reasoning: ${value}`);
 				}
 				reasoning = value;
@@ -90,7 +97,7 @@ function printHelp(): void {
 Options:
   --turns <n>          Number of user turns. Default: ${DEFAULT_TURNS}
   --transport <mode>   sse | websocket | websocket-cached | auto. Default: websocket-cached
-  --reasoning <level>  minimal | low | medium | high | xhigh. Default: low
+  --reasoning <level>  minimal | low | medium | high | xhigh | max. Default: low
   --max-tokens <n>     Max output tokens per model request. Default: ${DEFAULT_MAX_TOKENS}
   --session-id <id>    Session id for websocket/cache state
 `);

packages/ai/test/github-copilot-anthropic.test.ts

@@ -57,12 +57,14 @@ describe("Copilot Claude via Anthropic Messages", () => {
 
 	it("applies Copilot-specific adaptive thinking effort overrides", () => {
 		const opus47 = getModel("github-copilot", "claude-opus-4.7");
-		expect(opus47.thinkingLevelMap).toMatchObject({ minimal: "low", xhigh: "xhigh" });
+		expect(opus47.thinkingLevelMap).toMatchObject({ minimal: "low", xhigh: "xhigh", max: "max" });
 		expect(getSupportedThinkingLevels(opus47)).toContain("xhigh");
+		expect(getSupportedThinkingLevels(opus47)).toContain("max");
 
 		const sonnet46 = getModel("github-copilot", "claude-sonnet-4.6");
-		expect(sonnet46.thinkingLevelMap).toMatchObject({ minimal: "low", xhigh: "max" });
-		expect(getSupportedThinkingLevels(sonnet46)).toContain("xhigh");
+		expect(sonnet46.thinkingLevelMap).toMatchObject({ minimal: "low", max: "max" });
+		expect(getSupportedThinkingLevels(sonnet46)).toContain("max");
+		expect(getSupportedThinkingLevels(sonnet46)).not.toContain("xhigh");
 	});
 
 	it("uses Bearer auth, Copilot headers, and valid Anthropic Messages payload", async () => {

packages/ai/test/max-thinking.test.ts

@@ -0,0 +1,89 @@
+import { describe, expect, it } from "vitest";
+import { streamSimple as streamSimpleOpenAICodexResponses } from "../src/api/openai-codex-responses.ts";
+import { clampThinkingLevel, getModel, getSupportedThinkingLevels } from "../src/compat.ts";
+import type { Context, Model } from "../src/types.ts";
+
+function mockToken(): string {
+	const payload = Buffer.from(
+		JSON.stringify({ "https://api.openai.com/auth": { chatgpt_account_id: "acc_test" } }),
+		"utf8",
+	).toString("base64");
+	return `aaa.${payload}.bbb`;
+}
+
+describe("max thinking level", () => {
+	it("is opt-in for ordinary reasoning models", () => {
+		const model: Model<"openai-completions"> = {
+			id: "ordinary-reasoning",
+			name: "Ordinary Reasoning",
+			api: "openai-completions",
+			provider: "test",
+			baseUrl: "https://example.com/v1",
+			reasoning: true,
+			input: ["text"],
+			cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 },
+			contextWindow: 128000,
+			maxTokens: 4096,
+		};
+
+		expect(getSupportedThinkingLevels(model)).toEqual(["off", "minimal", "low", "medium", "high"]);
+		expect(clampThinkingLevel(model, "max")).toBe("high");
+	});
+
+	it.each(["gpt-5.6-luna", "gpt-5.6-sol", "gpt-5.6-terra"] as const)(
+		"exposes xhigh and max for openai-codex/%s",
+		(modelId) => {
+			const model = getModel("openai-codex", modelId);
+			expect(model).toBeDefined();
+			expect(model?.thinkingLevelMap).toMatchObject({ xhigh: "xhigh", max: "max" });
+			expect(getSupportedThinkingLevels(model!)).toEqual([
+				"off",
+				"minimal",
+				"low",
+				"medium",
+				"high",
+				"xhigh",
+				"max",
+			]);
+		},
+	);
+
+	it("supports a hole between high and max", () => {
+		const model: Model<"openai-completions"> = {
+			id: "high-and-max",
+			name: "High and Max",
+			api: "openai-completions",
+			provider: "test",
+			baseUrl: "https://example.com/v1",
+			reasoning: true,
+			thinkingLevelMap: { xhigh: null, max: "max" },
+			input: ["text"],
+			cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 },
+			contextWindow: 128000,
+			maxTokens: 4096,
+		};
+
+		expect(getSupportedThinkingLevels(model)).toEqual(["off", "minimal", "low", "medium", "high", "max"]);
+		expect(clampThinkingLevel(model, "xhigh")).toBe("max");
+	});
+
+	it("sends max to the Codex Responses API", async () => {
+		const model = getModel("openai-codex", "gpt-5.6-sol")!;
+		const context: Context = {
+			systemPrompt: "You are a helpful assistant.",
+			messages: [{ role: "user", content: "Hello", timestamp: Date.now() }],
+		};
+		let payload: unknown;
+
+		await streamSimpleOpenAICodexResponses(model, context, {
+			apiKey: mockToken(),
+			reasoning: "max",
+			onPayload: (request) => {
+				payload = request;
+				throw new Error("payload captured");
+			},
+		}).result();
+
+		expect(payload).toMatchObject({ reasoning: { effort: "max", summary: "auto" } });
+	});
+});

packages/ai/test/openai-completions-tool-choice.test.ts

@@ -305,7 +305,7 @@ describe("openai-completions tool_choice", () => {
 				low: "high",
 				medium: "high",
 				high: "high",
-				xhigh: "max",
+				max: "max",
 			});
 		}
 	});
@@ -316,7 +316,7 @@ describe("openai-completions tool_choice", () => {
 			{ reasoning: "low", effort: "high" },
 			{ reasoning: "medium", effort: "high" },
 			{ reasoning: "high", effort: "high" },
-			{ reasoning: "xhigh", effort: "max" },
+			{ reasoning: "max", effort: "max" },
 		] as const;
 
 		for (const testCase of cases) {

packages/ai/test/supports-xhigh.test.ts

@@ -2,35 +2,47 @@ import { describe, expect, it } from "vitest";
 import { getModel, getSupportedThinkingLevels } from "../src/compat.ts";
 
 describe("getSupportedThinkingLevels", () => {
-	it("includes xhigh for Anthropic Opus 4.6 on anthropic-messages API", () => {
+	it("includes max but not xhigh for Anthropic Opus 4.6 on anthropic-messages API", () => {
 		const model = getModel("anthropic", "claude-opus-4-6");
 		expect(model).toBeDefined();
-		expect(getSupportedThinkingLevels(model!)).toContain("xhigh");
+		expect(getSupportedThinkingLevels(model!)).toContain("max");
+		expect(getSupportedThinkingLevels(model!)).not.toContain("xhigh");
 	});
 
-	it("includes xhigh for Anthropic Opus 4.8 on anthropic-messages API", () => {
+	it("includes xhigh and max for Anthropic Opus 4.8 on anthropic-messages API", () => {
 		const model = getModel("anthropic", "claude-opus-4-8");
 		expect(model).toBeDefined();
 		expect(getSupportedThinkingLevels(model!)).toContain("xhigh");
+		expect(getSupportedThinkingLevels(model!)).toContain("max");
 	});
 
-	it("includes xhigh for Anthropic Opus 4.8 on anthropic-messages API", () => {
-		const model = getModel("anthropic", "claude-opus-4-8");
+	it("includes max but not xhigh for Anthropic Sonnet 4.6 on anthropic-messages API", () => {
+		const model = getModel("anthropic", "claude-sonnet-4-6");
+		expect(model).toBeDefined();
+		expect(getSupportedThinkingLevels(model!)).toContain("max");
+		expect(getSupportedThinkingLevels(model!)).not.toContain("xhigh");
+	});
+
+	it("includes xhigh and max for Anthropic Sonnet 5 on anthropic-messages API", () => {
+		const model = getModel("anthropic", "claude-sonnet-5");
 		expect(model).toBeDefined();
 		expect(getSupportedThinkingLevels(model!)).toContain("xhigh");
+		expect(getSupportedThinkingLevels(model!)).toContain("max");
 	});
 
-	it("includes xhigh but not off for Anthropic Claude Fable 5 on anthropic-messages API", () => {
+	it("includes xhigh and max but not off for Anthropic Claude Fable 5 on anthropic-messages API", () => {
 		const model = getModel("anthropic", "claude-fable-5");
 		expect(model).toBeDefined();
 		expect(getSupportedThinkingLevels(model!)).toContain("xhigh");
+		expect(getSupportedThinkingLevels(model!)).toContain("max");
 		expect(getSupportedThinkingLevels(model!)).not.toContain("off");
 	});
 
-	it("does not include xhigh for Claude Sonnet 4.5", () => {
+	it("does not include xhigh or max for Claude Sonnet 4.5", () => {
 		const model = getModel("anthropic", "claude-sonnet-4-5");
 		expect(model).toBeDefined();
 		expect(getSupportedThinkingLevels(model!)).not.toContain("xhigh");
+		expect(getSupportedThinkingLevels(model!)).not.toContain("max");
 	});
 
 	it.each(["gpt-5.4", "gpt-5.5", "gpt-5.6-sol", "gpt-5.6-terra", "gpt-5.6-luna"] as const)(
@@ -43,11 +55,19 @@ describe("getSupportedThinkingLevels", () => {
 	);
 
 	it.each(["gpt-5.6", "gpt-5.6-sol", "gpt-5.6-terra", "gpt-5.6-luna"] as const)(
-		"includes xhigh for OpenAI %s models",
+		"includes xhigh and max for OpenAI %s models",
 		(modelId) => {
 			const model = getModel("openai", modelId);
 			expect(model).toBeDefined();
-			expect(getSupportedThinkingLevels(model!)).toContain("xhigh");
+			expect(getSupportedThinkingLevels(model!)).toEqual([
+				"off",
+				"minimal",
+				"low",
+				"medium",
+				"high",
+				"xhigh",
+				"max",
+			]);
 		},
 	);
 
@@ -63,16 +83,16 @@ describe("getSupportedThinkingLevels", () => {
 		expect(getSupportedThinkingLevels(model!)).toEqual(["medium", "high", "xhigh"]);
 	});
 
-	it("includes only high/xhigh plus off for DeepSeek V4 Flash on the DeepSeek provider", () => {
+	it("includes only high/max plus off for DeepSeek V4 Flash on the DeepSeek provider", () => {
 		const model = getModel("deepseek", "deepseek-v4-flash");
 		expect(model).toBeDefined();
-		expect(getSupportedThinkingLevels(model!)).toEqual(["off", "high", "xhigh"]);
+		expect(getSupportedThinkingLevels(model!)).toEqual(["off", "high", "max"]);
 	});
 
-	it("includes only high/xhigh plus off for DeepSeek V4 Flash on opencode-go", () => {
+	it("includes only high/max plus off for DeepSeek V4 Flash on opencode-go", () => {
 		const model = getModel("opencode-go", "deepseek-v4-flash");
 		expect(model).toBeDefined();
-		expect(getSupportedThinkingLevels(model!)).toEqual(["off", "high", "xhigh"]);
+		expect(getSupportedThinkingLevels(model!)).toEqual(["off", "high", "max"]);
 	});
 
 	it("includes only high plus off for OpenCode Go Kimi K2.6", () => {
@@ -102,16 +122,18 @@ describe("getSupportedThinkingLevels", () => {
 		expect(getSupportedThinkingLevels(model!)).toEqual(["off", "high", "xhigh"]);
 	});
 
-	it("includes xhigh for OpenRouter Opus 4.6 (openai-completions API)", () => {
+	it("includes max but not xhigh for OpenRouter Opus 4.6 (openai-completions API)", () => {
 		const model = getModel("openrouter", "anthropic/claude-opus-4.6");
 		expect(model).toBeDefined();
-		expect(getSupportedThinkingLevels(model!)).toContain("xhigh");
+		expect(getSupportedThinkingLevels(model!)).toContain("max");
+		expect(getSupportedThinkingLevels(model!)).not.toContain("xhigh");
 	});
 
-	it("includes xhigh but not off for Bedrock Claude Fable 5", () => {
+	it("includes xhigh and max but not off for Bedrock Claude Fable 5", () => {
 		const model = getModel("amazon-bedrock", "global.anthropic.claude-fable-5");
 		expect(model).toBeDefined();
 		expect(getSupportedThinkingLevels(model!)).toContain("xhigh");
+		expect(getSupportedThinkingLevels(model!)).toContain("max");
 		expect(getSupportedThinkingLevels(model!)).not.toContain("off");
 	});
 });

packages/coding-agent/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Added
+
+- Added the opt-in `max` thinking level across CLI, SDK, RPC, model selection, and themes. Custom themes can define `thinkingMax`; existing themes fall back to `thinkingXhigh`.
+
 ## [0.80.5] - 2026-07-09
 
 ## [0.80.4] - 2026-07-09

packages/coding-agent/README.md

@@ -551,7 +551,7 @@ cat README.md | pi -p "Summarize this text"
 | `--provider <name>` | Provider (anthropic, openai, google, etc.) |
 | `--model <pattern>` | Model pattern or ID (supports `provider/id` and optional `:<thinking>`) |
 | `--api-key <key>` | API key (overrides env vars) |
-| `--thinking <level>` | `off`, `minimal`, `low`, `medium`, `high`, `xhigh` |
+| `--thinking <level>` | `off`, `minimal`, `low`, `medium`, `high`, `xhigh`, `max` |
 | `--models <patterns>` | Comma-separated patterns for Ctrl+P cycling |
 | `--list-models [search]` | List available models |
 

packages/coding-agent/docs/custom-provider.md

@@ -204,7 +204,7 @@ The `api` field determines which streaming implementation is used:
 | `google-vertex` | Google Vertex AI API |
 | `bedrock-converse-stream` | Amazon Bedrock Converse API |
 
-Most OpenAI-compatible providers work with `openai-completions`. Use model-level `thinkingLevelMap` for model-specific thinking levels, and `compat` for provider quirks:
+Most OpenAI-compatible providers work with `openai-completions`. Use model-level `thinkingLevelMap` for model-specific thinking levels, and `compat` for provider quirks. The `xhigh` and `max` levels are opt-in, require non-null map entries, and may be separated by unsupported holes:
 
 ```typescript
 models: [{
@@ -216,7 +216,8 @@ models: [{
     low: null,
     medium: null,
     high: "default",
-    xhigh: "max"
+    xhigh: null,
+    max: "max"
   },
   compat: {
     supportsDeveloperRole: false,   // use "system" instead of "developer"
@@ -684,7 +685,7 @@ interface ProviderModelConfig {
   reasoning: boolean;
 
   /** Maps pi thinking levels to provider/model-specific values; null marks a level unsupported. */
-  thinkingLevelMap?: Partial<Record<"off" | "minimal" | "low" | "medium" | "high" | "xhigh", string | null>>;
+  thinkingLevelMap?: Partial<Record<"off" | "minimal" | "low" | "medium" | "high" | "xhigh" | "max", string | null>>;
 
   /** Supported input types. */
   input: ("text" | "image")[];

packages/coding-agent/docs/extensions.md

@@ -1657,7 +1657,7 @@ if (model) {
 Get or set the thinking level. Level is clamped to model capabilities (non-reasoning models always use "off"). Changes emit `thinking_level_select`.
 
 ```typescript
-const current = pi.getThinkingLevel();  // "off" | "minimal" | "low" | "medium" | "high" | "xhigh"
+const current = pi.getThinkingLevel();  // "off" | "minimal" | "low" | "medium" | "high" | "xhigh" | "max"
 pi.setThinkingLevel("high");
 ```
 

packages/coding-agent/docs/models.md

@@ -214,13 +214,13 @@ Current behavior:
 
 ### Thinking Level Map
 
-Use `thinkingLevelMap` on a model to describe model-specific thinking controls. Keys are pi thinking levels: `off`, `minimal`, `low`, `medium`, `high`, `xhigh`.
+Use `thinkingLevelMap` on a model to describe model-specific thinking controls. Keys are pi thinking levels: `off`, `minimal`, `low`, `medium`, `high`, `xhigh`, `max`. Maps may contain holes; for example, a model can expose `high` and `max` without exposing `xhigh`.
 
 Values are tristate:
 
 | Value | Meaning |
 |-------|---------|
-| omitted | Level is supported and uses the provider's default mapping |
+| omitted | Standard levels through `high` use the provider's default mapping; extended `xhigh` and `max` levels are unsupported |
 | string | Level is supported and this value is sent to the provider |
 | `null` | Level is unsupported and hidden/skipped/clamped away |
 
@@ -235,7 +235,8 @@ Example for a model that only supports off, high, and max reasoning:
     "low": null,
     "medium": null,
     "high": "high",
-    "xhigh": "max"
+    "xhigh": null,
+    "max": "max"
   }
 }
 ```

packages/coding-agent/docs/rpc.md

@@ -286,9 +286,9 @@ Set the reasoning/thinking level for models that support it.
 {"type": "set_thinking_level", "level": "high"}
 ```
 
-Levels: `"off"`, `"minimal"`, `"low"`, `"medium"`, `"high"`, `"xhigh"`
+Levels: `"off"`, `"minimal"`, `"low"`, `"medium"`, `"high"`, `"xhigh"`, `"max"`
 
-Note: `"xhigh"` is only supported by OpenAI codex-max models.
+`"xhigh"` and `"max"` are exposed only when supported by the selected model. Some models, including GPT-5.6, expose both.
 
 Response:
 ```json

packages/coding-agent/docs/sdk.md

@@ -387,7 +387,7 @@ const available = await modelRegistry.getAvailable();
 
 const { session } = await createAgentSession({
   model: opus,
-  thinkingLevel: "medium", // off, minimal, low, medium, high, xhigh
+  thinkingLevel: "medium", // off, minimal, low, medium, high, xhigh, max
   
   // Models for cycling (Ctrl+P in interactive mode)
   scopedModels: [

packages/coding-agent/docs/settings.md

@@ -29,7 +29,7 @@ Use `/trust` in interactive mode to save a project trust decision for future ses
 |---------|------|---------|-------------|
 | `defaultProvider` | string | - | Default provider (e.g., `"anthropic"`, `"openai"`) |
 | `defaultModel` | string | - | Default model ID |
-| `defaultThinkingLevel` | string | - | `"off"`, `"minimal"`, `"low"`, `"medium"`, `"high"`, `"xhigh"` |
+| `defaultThinkingLevel` | string | - | `"off"`, `"minimal"`, `"low"`, `"medium"`, `"high"`, `"xhigh"`, `"max"` |
 | `hideThinkingBlock` | boolean | `false` | Hide thinking blocks in output |
 | `showCacheMissNotices` | boolean | `false` | Show transcript notices for significant prompt-cache misses |
 | `thinkingBudgets` | object | - | Custom token budgets per thinking level |

packages/coding-agent/docs/themes.md

@@ -109,6 +109,7 @@ vim ~/.pi/agent/themes/my-theme.json
     "thinkingMedium": "#00ffff",
     "thinkingHigh": "#ff00ff",
     "thinkingXhigh": "#ff0000",
+    "thinkingMax": "#ff0088",
     "bashMode": "#ffaa00"
   }
 }
@@ -139,13 +140,13 @@ vim ~/.pi/agent/themes/my-theme.json
 
 - `name` is required, must be unique, and must not contain `/`.
 - `vars` is optional. Define reusable colors here, then reference them in `colors`.
-- `colors` must define all 51 required tokens.
+- `colors` must define all 51 required tokens. `thinkingMax` is optional and falls back to `thinkingXhigh`.
 
 The `$schema` field enables editor auto-completion and validation.
 
 ## Color Tokens
 
-Every theme must define all 51 color tokens. There are no optional colors.
+Every theme must define all 51 required color tokens. `thinkingMax` is optional for compatibility with existing themes; when omitted, it uses `thinkingXhigh`.
 
 ### Core UI (11 colors)
 
@@ -216,7 +217,7 @@ Every theme must define all 51 color tokens. There are no optional colors.
 | `syntaxOperator` | Operators |
 | `syntaxPunctuation` | Punctuation |
 
-### Thinking Level Borders (6 colors)
+### Thinking Level Borders (6 required, 1 optional)
 
 Editor border colors indicating thinking level (visual hierarchy from subtle to prominent):
 
@@ -228,6 +229,7 @@ Editor border colors indicating thinking level (visual hierarchy from subtle to
 | `thinkingMedium` | Medium thinking |
 | `thinkingHigh` | High thinking |
 | `thinkingXhigh` | Extra high thinking |
+| `thinkingMax` | Maximum thinking; optional, falls back to `thinkingXhigh` |
 
 ### Bash Mode (1 color)
 

packages/coding-agent/docs/tui.md

@@ -424,7 +424,7 @@ renderResult(result, options, theme, context) {
 | Diffs | `toolDiffAdded`, `toolDiffRemoved`, `toolDiffContext` |
 | Markdown | `mdHeading`, `mdLink`, `mdLinkUrl`, `mdCode`, `mdCodeBlock`, `mdCodeBlockBorder`, `mdQuote`, `mdQuoteBorder`, `mdHr`, `mdListBullet` |
 | Syntax | `syntaxComment`, `syntaxKeyword`, `syntaxFunction`, `syntaxVariable`, `syntaxString`, `syntaxNumber`, `syntaxType`, `syntaxOperator`, `syntaxPunctuation` |
-| Thinking | `thinkingOff`, `thinkingMinimal`, `thinkingLow`, `thinkingMedium`, `thinkingHigh`, `thinkingXhigh` |
+| Thinking | `thinkingOff`, `thinkingMinimal`, `thinkingLow`, `thinkingMedium`, `thinkingHigh`, `thinkingXhigh`, `thinkingMax` |
 | Modes | `bashMode` |
 
 **Background colors** (`theme.bg(color, text)`):

packages/coding-agent/docs/usage.md

@@ -183,7 +183,7 @@ cat README.md | pi -p "Summarize this text"
 | `--provider <name>` | Provider, such as `anthropic`, `openai`, or `google` |
 | `--model <pattern>` | Model pattern or ID; supports `provider/id` and optional `:<thinking>` |
 | `--api-key <key>` | API key, overriding environment variables |
-| `--thinking <level>` | `off`, `minimal`, `low`, `medium`, `high`, `xhigh` |
+| `--thinking <level>` | `off`, `minimal`, `low`, `medium`, `high`, `xhigh`, `max` |
 | `--models <patterns>` | Comma-separated patterns for Ctrl+P cycling |
 | `--list-models [search]` | List available models |
 

packages/coding-agent/examples/extensions/preset.ts

@@ -52,7 +52,7 @@ interface Preset {
 	/** Model ID (e.g., "claude-sonnet-4-5") */
 	model?: string;
 	/** Thinking level */
-	thinkingLevel?: "off" | "minimal" | "low" | "medium" | "high" | "xhigh";
+	thinkingLevel?: "off" | "minimal" | "low" | "medium" | "high" | "xhigh" | "max";
 	/** Tools to enable (replaces default set) */
 	tools?: string[];
 	/** Instructions to append to system prompt */
@@ -100,7 +100,7 @@ function loadPresets(cwd: string): PresetsConfig {
 
 interface OriginalState {
 	model: Model<Api> | undefined;
-	thinkingLevel: "off" | "minimal" | "low" | "medium" | "high" | "xhigh";
+	thinkingLevel: "off" | "minimal" | "low" | "medium" | "high" | "xhigh" | "max";
 	tools: string[];
 }
 

packages/coding-agent/src/cli/args.ts

@@ -54,7 +54,7 @@ export interface Args {
 	diagnostics: Array<{ type: "warning" | "error"; message: string }>;
 }
 
-const VALID_THINKING_LEVELS = ["off", "minimal", "low", "medium", "high", "xhigh"] as const;
+const VALID_THINKING_LEVELS = ["off", "minimal", "low", "medium", "high", "xhigh", "max"] as const;
 
 export function isValidThinkingLevel(level: string): level is ThinkingLevel {
 	return VALID_THINKING_LEVELS.includes(level as ThinkingLevel);
@@ -258,7 +258,7 @@ ${chalk.bold("Options:")}
                                  Applies to built-in, extension, and custom tools
   --exclude-tools, -xt <tools>   Comma-separated denylist of tool names to disable
                                  Applies to built-in, extension, and custom tools
-  --thinking <level>             Set thinking level: off, minimal, low, medium, high, xhigh
+  --thinking <level>             Set thinking level: off, minimal, low, medium, high, xhigh, max
   --extension, -e <path>         Load an extension file (can be used multiple times)
   --no-extensions, -ne           Disable extension discovery (explicit -e paths still work)
   --skill <path>                 Load a skill file or directory (can be used multiple times)

packages/coding-agent/src/core/model-registry.ts

@@ -94,6 +94,7 @@ const ThinkingLevelMapSchema = Type.Object({
 	medium: Type.Optional(ThinkingLevelMapValueSchema),
 	high: Type.Optional(ThinkingLevelMapValueSchema),
 	xhigh: Type.Optional(ThinkingLevelMapValueSchema),
+	max: Type.Optional(ThinkingLevelMapValueSchema),
 });
 
 const ChatTemplateKwargScalarSchema = Type.Union([Type.String(), Type.Number(), Type.Boolean(), Type.Null()]);

packages/coding-agent/src/core/settings-manager.ts

@@ -1,3 +1,4 @@
+import type { ThinkingLevel } from "@earendil-works/pi-agent-core";
 import type { Transport } from "@earendil-works/pi-ai";
 import { randomUUID } from "crypto";
 import { existsSync, mkdirSync, readFileSync, writeFileSync } from "fs";
@@ -83,7 +84,7 @@ export interface Settings {
 	lastChangelogVersion?: string;
 	defaultProvider?: string;
 	defaultModel?: string;
-	defaultThinkingLevel?: "off" | "minimal" | "low" | "medium" | "high" | "xhigh";
+	defaultThinkingLevel?: ThinkingLevel;
 	transport?: TransportSetting; // default: "auto"
 	steeringMode?: "all" | "one-at-a-time";
 	followUpMode?: "all" | "one-at-a-time";
@@ -736,11 +737,11 @@ export class SettingsManager {
 		this.save();
 	}
 
-	getDefaultThinkingLevel(): "off" | "minimal" | "low" | "medium" | "high" | "xhigh" | undefined {
+	getDefaultThinkingLevel(): ThinkingLevel | undefined {
 		return this.settings.defaultThinkingLevel;
 	}
 
-	setDefaultThinkingLevel(level: "off" | "minimal" | "low" | "medium" | "high" | "xhigh"): void {
+	setDefaultThinkingLevel(level: ThinkingLevel): void {
 		this.globalSettings.defaultThinkingLevel = level;
 		this.markModified("defaultThinkingLevel");
 		this.save();

packages/coding-agent/src/modes/interactive/components/settings-selector.ts

@@ -35,7 +35,8 @@ const THINKING_DESCRIPTIONS: Record<ThinkingLevel, string> = {
 	low: "Light reasoning (~2k tokens)",
 	medium: "Moderate reasoning (~8k tokens)",
 	high: "Deep reasoning (~16k tokens)",
-	xhigh: "Maximum reasoning (~32k tokens)",
+	xhigh: "Extra-high reasoning (~32k tokens)",
+	max: "Maximum reasoning",
 };
 
 const DEFAULT_PROJECT_TRUST_LABELS: Record<DefaultProjectTrust, string> = {

packages/coding-agent/src/modes/interactive/components/thinking-selector.ts

@@ -14,7 +14,8 @@ const LEVEL_DESCRIPTIONS: Record<ThinkingLevel, string> = {
 	low: "Light reasoning (~2k tokens)",
 	medium: "Moderate reasoning (~8k tokens)",
 	high: "Deep reasoning (~16k tokens)",
-	xhigh: "Maximum reasoning (~32k tokens)",
+	xhigh: "Extra-high reasoning (~32k tokens)",
+	max: "Maximum reasoning",
 };
 
 /**

packages/coding-agent/src/modes/interactive/theme/dark.json

@@ -75,6 +75,7 @@
 		"thinkingMedium": "#81a2be",
 		"thinkingHigh": "#b294bb",
 		"thinkingXhigh": "#d183e8",
+		"thinkingMax": "#ff5fff",
 
 		"bashMode": "green"
 	},

packages/coding-agent/src/modes/interactive/theme/light.json

@@ -74,6 +74,7 @@
 		"thinkingMedium": "teal",
 		"thinkingHigh": "#875f87",
 		"thinkingXhigh": "#8b008b",
+		"thinkingMax": "#af005f",
 
 		"bashMode": "green"
 	},

packages/coding-agent/src/modes/interactive/theme/theme-schema.json

@@ -34,7 +34,7 @@
 		},
 		"colors": {
 			"type": "object",
-			"description": "Theme color definitions (all required)",
+			"description": "Theme color definitions (thinkingMax is optional and falls back to thinkingXhigh)",
 			"required": [
 				"accent",
 				"border",
@@ -287,7 +287,11 @@
 				},
 				"thinkingXhigh": {
 					"$ref": "#/$defs/colorValue",
-					"description": "Thinking level border: xhigh (OpenAI codex-max only)"
+					"description": "Thinking level border: xhigh"
+				},
+				"thinkingMax": {
+					"$ref": "#/$defs/colorValue",
+					"description": "Thinking level border: max (falls back to thinkingXhigh when omitted)"
 				},
 				"bashMode": {
 					"$ref": "#/$defs/colorValue",

packages/coding-agent/src/modes/interactive/theme/theme.ts

@@ -1,5 +1,6 @@
 import * as fs from "node:fs";
 import * as path from "node:path";
+import type { ThinkingLevel } from "@earendil-works/pi-agent-core";
 import {
 	type EditorTheme,
 	getCapabilities,
@@ -88,6 +89,7 @@ const ThemeJsonSchema = Type.Object({
 		thinkingMedium: ColorValueSchema,
 		thinkingHigh: ColorValueSchema,
 		thinkingXhigh: ColorValueSchema,
+		thinkingMax: Type.Optional(ColorValueSchema),
 		// Bash Mode (1 color)
 		bashMode: ColorValueSchema,
 	}),
@@ -149,6 +151,7 @@ export type ThemeColor =
 	| "thinkingMedium"
 	| "thinkingHigh"
 	| "thinkingXhigh"
+	| "thinkingMax"
 	| "bashMode";
 
 export type ThemeBg =
@@ -316,6 +319,10 @@ function resolveThemeColors<T extends Record<string, ColorValue>>(
 	return resolved as Record<keyof T, string | number>;
 }
 
+function withThemeColorFallbacks(colors: ThemeJson["colors"]): ThemeJson["colors"] & { thinkingMax: ColorValue } {
+	return { ...colors, thinkingMax: colors.thinkingMax ?? colors.thinkingXhigh };
+}
+
 // ============================================================================
 // Theme Class
 // ============================================================================
@@ -339,7 +346,8 @@ export class Theme {
 		this.sourceInfo = options.sourceInfo;
 		this.mode = mode;
 		this.fgColors = new Map();
-		for (const [key, value] of Object.entries(fgColors) as [ThemeColor, string | number][]) {
+		const colors = { ...fgColors, thinkingMax: fgColors.thinkingMax ?? fgColors.thinkingXhigh };
+		for (const [key, value] of Object.entries(colors) as [ThemeColor, string | number][]) {
 			this.fgColors.set(key, fgAnsi(value, mode));
 		}
 		this.bgColors = new Map();
@@ -396,7 +404,7 @@ export class Theme {
 		return this.mode;
 	}
 
-	getThinkingBorderColor(level: "off" | "minimal" | "low" | "medium" | "high" | "xhigh"): (str: string) => string {
+	getThinkingBorderColor(level: ThinkingLevel): (str: string) => string {
 		// Map thinking levels to dedicated theme colors
 		switch (level) {
 			case "off":
@@ -411,6 +419,8 @@ export class Theme {
 				return (str: string) => this.fg("thinkingHigh", str);
 			case "xhigh":
 				return (str: string) => this.fg("thinkingXhigh", str);
+			case "max":
+				return (str: string) => this.fg("thinkingMax", str);
 			default:
 				return (str: string) => this.fg("thinkingOff", str);
 		}
@@ -586,7 +596,7 @@ function loadThemeJson(name: string): ThemeJson {
 
 function createTheme(themeJson: ThemeJson, mode?: ColorMode, sourcePath?: string): Theme {
 	const colorMode = mode ?? (getCapabilities().trueColor ? "truecolor" : "256color");
-	const resolvedColors = resolveThemeColors(themeJson.colors, themeJson.vars);
+	const resolvedColors = resolveThemeColors(withThemeColorFallbacks(themeJson.colors), themeJson.vars);
 	const fgColors: Record<ThemeColor, string | number> = {} as Record<ThemeColor, string | number>;
 	const bgColors: Record<ThemeBg, string | number> = {} as Record<ThemeBg, string | number>;
 	const bgColorKeys: Set<string> = new Set([
@@ -1013,7 +1023,7 @@ export function getResolvedThemeColors(themeName?: string): Record<string, strin
 	const name = themeName ?? currentThemeName ?? getDefaultTheme();
 	const isLight = name === "light";
 	const themeJson = loadThemeJson(name);
-	const resolved = resolveThemeColors(themeJson.colors, themeJson.vars);
+	const resolved = resolveThemeColors(withThemeColorFallbacks(themeJson.colors), themeJson.vars);
 
 	// Default text color for empty values (terminal uses default fg color)
 	const defaultText = isLight ? "#000000" : "#e5e5e7";

packages/coding-agent/test/max-thinking.test.ts

@@ -0,0 +1,45 @@
+import { mkdtempSync, readFileSync, rmSync, writeFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { dirname, join } from "node:path";
+import { fileURLToPath } from "node:url";
+import { afterEach, describe, expect, it } from "vitest";
+import { isValidThinkingLevel } from "../src/cli/args.ts";
+import { SettingsManager } from "../src/core/settings-manager.ts";
+import { loadThemeFromPath } from "../src/modes/interactive/theme/theme.ts";
+
+const tempDirs: string[] = [];
+
+afterEach(() => {
+	for (const dir of tempDirs.splice(0)) {
+		rmSync(dir, { recursive: true, force: true });
+	}
+});
+
+describe("max thinking level", () => {
+	it("is accepted by CLI and settings", async () => {
+		expect(isValidThinkingLevel("max")).toBe(true);
+
+		const settings = SettingsManager.inMemory();
+		settings.setDefaultThinkingLevel("max");
+		await settings.flush();
+		expect(settings.getDefaultThinkingLevel()).toBe("max");
+	});
+
+	it("falls back to thinkingXhigh for legacy themes", () => {
+		const testDir = mkdtempSync(join(tmpdir(), "pi-max-theme-"));
+		tempDirs.push(testDir);
+		const currentDir = dirname(fileURLToPath(import.meta.url));
+		const darkTheme = JSON.parse(
+			readFileSync(join(currentDir, "../src/modes/interactive/theme/dark.json"), "utf8"),
+		) as { name: string; colors: Record<string, unknown> };
+		darkTheme.name = "legacy-theme";
+		delete darkTheme.colors.thinkingMax;
+		const themePath = join(testDir, "legacy-theme.json");
+		writeFileSync(themePath, JSON.stringify(darkTheme));
+
+		const legacyTheme = loadThemeFromPath(themePath);
+		expect(legacyTheme.getThinkingBorderColor("max")("border")).toBe(
+			legacyTheme.getThinkingBorderColor("xhigh")("border"),
+		);
+	});
+});

packages/coding-agent/test/model-resolver.test.ts

@@ -107,7 +107,7 @@ describe("parseModelPattern", () => {
 		});
 
 		test("all valid thinking levels work", () => {
-			for (const level of ["off", "minimal", "low", "medium", "high", "xhigh"]) {
+			for (const level of ["off", "minimal", "low", "medium", "high", "xhigh", "max"]) {
 				const result = parseModelPattern(`sonnet:${level}`, allModels);
 				expect(result.model?.id).toBe("claude-sonnet-4-5");
 				expect(result.thinkingLevel).toBe(level);
@@ -520,7 +520,7 @@ describe("resolveCliModel", () => {
 				getAll: () => modelsWithNeuralwatt,
 			} as unknown as Parameters<typeof resolveCliModel>[0]["modelRegistry"];
 
-			for (const level of ["off", "minimal", "low", "medium", "high", "xhigh"]) {
+			for (const level of ["off", "minimal", "low", "medium", "high", "xhigh", "max"]) {
 				const result = resolveCliModel({
 					cliModel: `neuralwatt/zai-org/GLM-5.1-FP8:${level}`,
 					modelRegistry: registry,

packages/coding-agent/test/suite/agent-session-model-extension.test.ts

@@ -78,6 +78,26 @@ describe("AgentSession model and extension characterization", () => {
 		expect(harness.session.cycleThinkingLevel()).toBeUndefined();
 	});
 
+	it("cycles xhigh before max when both are supported", async () => {
+		const harness = await createHarness({ models: [{ id: "faux-1", reasoning: true }] });
+		harnesses.push(harness);
+		harness.getModel().thinkingLevelMap = { xhigh: "xhigh", max: "max" };
+
+		expect(harness.session.getAvailableThinkingLevels()).toEqual([
+			"off",
+			"minimal",
+			"low",
+			"medium",
+			"high",
+			"xhigh",
+			"max",
+		]);
+		harness.session.setThinkingLevel("high");
+		expect(harness.session.cycleThinkingLevel()).toBe("xhigh");
+		expect(harness.session.cycleThinkingLevel()).toBe("max");
+		expect(harness.session.cycleThinkingLevel()).toBe("off");
+	});
+
 	it("throws when setModel is called without configured auth", async () => {
 		const harness = await createHarness({
 			models: [