feat(ai): add max thinking level

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 |