docs: add experimental tag

Author: ingim

website/docs/guide/context/pages.mdx

@@ -192,7 +192,7 @@ raw.truncate_working_page_tokens(n);    // drop the last n tokens within the wor
 
 Working pages must be full (every slot written) before they can commit. Calling `commit_working_pages(k)` while the k-th page is still partial returns an error. Most code lets `flush()` decide when to commit; the manual form is for hand-written forward-pass loops.
 
-For when to use these operations, see [Inputs: tokens, positions, masks](../forward/inputs).
+For when to use these operations, see [Tokens, positions, and masks](../forward/inputs).
 
 ## When pages get freed
 

website/docs/guide/context/scheduling.mdx

@@ -9,6 +9,10 @@ import TabItem from '@theme/TabItem';
 
 # Scheduling and budgets
 
+:::warning[Experimental]
+The credit auction and bidding API are a prototype. Interfaces, defaults, and capabilities change frequently.
+:::
+
 Pie's engine schedules forward passes across all live processes via a per-step credit auction. Each context bids for compute on every tick, and the engine fills its batch by clearing the highest bids first. This page covers the bidding API. **Most inferlets do not need to touch it.** The default `Generator` auto-bids using a budget-exhausting strategy that spreads the wallet over the horizon. Read on if you want to write a custom bid strategy or understand what the default is doing. Read this after [Pages](./pages).
 
 ## Why credits

website/docs/guide/forward/adapters.mdx

@@ -9,6 +9,10 @@ import TabItem from '@theme/TabItem';
 
 # Adapters
 
+:::warning[Experimental]
+Adapter support is a prototype. Interfaces, defaults, and capabilities change frequently.
+:::
+
 LoRA adapters are runtime-managed overlays scoped to a model. The full lifecycle (create, open, fork, save, load, destroy) is available in all three SDKs. This page covers using an adapter at inference. Read this after [The forward pass](./overview).
 
 :::note[Running on the dummy driver?]

website/docs/guide/forward/inputs.mdx

@@ -1,10 +1,10 @@
 ---
-title: "Inputs: tokens, positions, masks"
+title: "Tokens, positions, and masks"
 description: Drive the input side of a forward pass with tokens, custom positions, and BRLE attention masks
 sidebar_position: 2
 ---
 
-# Inputs: tokens, positions, masks
+# Tokens, positions, and masks
 
 A forward pass takes a list of input positions, the token IDs at those positions, and an optional attention mask. This page covers the three input modalities. Read this after [The forward pass](./overview).
 

website/docs/guide/forward/overview.mdx

@@ -113,14 +113,14 @@ The handles are typed: `out.token(probe_handle)` does not compile. Mismatched ac
 
 ## What this section covers
 
-- [Inputs: tokens, positions, masks](./inputs). Building the input side of a forward pass.
+- [Tokens, positions, and masks](./inputs). Building the input side of a forward pass.
 - [Samplers and probabilities](./samplers). Every `Sampler` kind and every `Probe` kind.
 - [Constrained generation](./constrained). Logit masks driven by JSON Schema, regex, EBNF, and custom grammars.
 - [Adapters](./adapters). LoRA adapters scoped to a model.
 - [Speculative decoding](./speculation). System speculation and the `Speculator` trait.
 
 ## Next
 
-- [Inputs: tokens, positions, masks](./inputs).
+- [Tokens, positions, and masks](./inputs).
 - [Samplers and probabilities](./samplers).
 - [Generation overview](../decoder/overview): the layer that runs `forward()` in a loop for you.

website/docs/guide/io/mcp.mdx

@@ -9,6 +9,10 @@ import TabItem from '@theme/TabItem';
 
 # MCP
 
+:::warning[Experimental]
+MCP support is a prototype. Interfaces, defaults, and capabilities change frequently.
+:::
+
 The [Model Context Protocol](https://modelcontextprotocol.io/) is an open standard for exposing tools, resources, and prompt templates to LLM applications. Pie ships an MCP client. Inferlets discover and call MCP servers without writing transport code. Read this after [Tool-call parser](../decoder/tool-calling).
 
 There are two sides to MCP in Pie:

website/docs/reference/bakery.mdx

@@ -5,6 +5,10 @@ description: Reference for the bakery CLI (scaffold, build, publish inferlets)
 
 # Bakery
 
+:::warning[Experimental]
+Bakery is a prototype. Interfaces, defaults, and capabilities change frequently.
+:::
+
 `bakery` is the developer-side CLI for inferlets. It wraps the Cargo / npm build, talks to the Pie registry, and produces packaged WASM artifacts.
 
 For the end-to-end workflow narrative, see [Your first inferlet](../guide/first-inferlet) (build) and [Deploy and publish](../guide/deploy/serve) (publish). This page is the command reference.

website/docs/reference/drivers/sglang.mdx

@@ -6,6 +6,10 @@ sidebar_position: 5
 
 # SGLang
 
+:::warning[Experimental]
+The SGLang driver is a prototype. Interfaces, defaults, and capabilities change frequently.
+:::
+
 `type = "sglang"`. A subprocess Python driver that delegates the forward pass to SGLang. Pie wraps SGLang's `ServerArgs`; field names match SGLang exactly, so values pass through unchanged.
 
 Use this driver to run a model that the embedded [`cuda_native` and `dev`](./cuda) drivers do not yet implement, or to run against SGLang's attention kernels and its n-gram speculative decoding.

website/docs/reference/drivers/vllm.mdx

@@ -6,6 +6,10 @@ sidebar_position: 4
 
 # vLLM
 
+:::warning[Experimental]
+The vLLM driver is a prototype. Interfaces, defaults, and capabilities change frequently.
+:::
+
 `type = "vllm"`. A subprocess Python driver that delegates the forward pass to vLLM. Pie wraps vLLM's `EngineArgs`; field names match vLLM exactly, so values pass through unchanged.
 
 Use this driver to run a model that the embedded [`cuda_native` and `dev`](./cuda) drivers do not yet implement, or to run against vLLM's attention kernels.

website/sidebars.ts

@@ -65,7 +65,7 @@ const sidebars: SidebarsConfig = {
         'guide/context/overview',
         'guide/context/pages',
         'guide/context/sharing',
-        'guide/context/scheduling',
+        {type: 'doc', id: 'guide/context/scheduling', className: 'sidebar-experimental'},
       ],
     },
     {
@@ -77,8 +77,8 @@ const sidebars: SidebarsConfig = {
         'guide/forward/inputs',
         'guide/forward/samplers',
         'guide/forward/constrained',
-        'guide/forward/adapters',
         'guide/forward/speculation',
+        {type: 'doc', id: 'guide/forward/adapters', className: 'sidebar-experimental'},
       ],
     },
     {
@@ -103,7 +103,7 @@ const sidebars: SidebarsConfig = {
         'guide/io/messaging',
         'guide/io/http',
         'guide/io/filesystem',
-        'guide/io/mcp',
+        {type: 'doc', id: 'guide/io/mcp', className: 'sidebar-experimental'},
       ],
     },
     {
@@ -148,7 +148,7 @@ const sidebars: SidebarsConfig = {
       collapsed: false,
       items: [
         'reference/pie',
-        'reference/bakery',
+        {type: 'doc', id: 'reference/bakery', className: 'sidebar-experimental'},
         'reference/pie-client',
       ],
     },
@@ -159,8 +159,8 @@ const sidebars: SidebarsConfig = {
       items: [
         'reference/drivers/cuda',
         'reference/drivers/portable',
-        'reference/drivers/vllm',
-        'reference/drivers/sglang',
+        {type: 'doc', id: 'reference/drivers/vllm', className: 'sidebar-experimental'},
+        {type: 'doc', id: 'reference/drivers/sglang', className: 'sidebar-experimental'},
       ],
     },
     {