[DOCS] examples/settings has no example for per-request context cost

### Documentation Type

Missing documentation (feature not documented)

### Documentation Location

examples/settings/README.md

### Section/Topic

examples/settings - no example covers per-request context cost

### Current Documentation

`examples/settings/` covers permission and sandbox posture (`settings-lax.json`,
`settings-strict.json`, `settings-bash-sandbox.json`). Nothing covers a cost every request
pays: eagerly-loaded built-in tool schemas.

Nothing in the README states that `permissions.deny` on a built-in also keeps that tool's
schema out of context. An admin reading the table can reasonably assume denying a tool only
gates the call.

### What's Wrong or Missing?

Several built-in tools are opt-in features whose schemas are sent on every request whether
or not the organization uses them. `Workflow` is the largest single item in the tool block.

Measured on v2.1.247, `--model opus`, first API request of a headless run, summing
`input_tokens + cache_creation_input_tokens + cache_read_input_tokens`, all rows back to
back in one unchanged environment:

| settings | input tokens | reclaimed |
|---|---|---|
| none (baseline) | 23,052 | - |
| `deny: [Workflow]` | 15,152 | 7,900 |
| five opt-in tools denied | 12,166 | 10,886 (-47%) |

The reclaimed column is the reproducible figure; absolute totals also carry the local
`CLAUDE.md`, memory files and MCP definitions.

### Suggested Improvement

Add a fourth example plus one table column and one `Tips` bullet. Patch is ready on a public
branch, since this repo does not currently accept pull requests from outside accounts
(`CreatePullRequest` returns `FORBIDDEN`; the same call on `anthropics/anthropic-sdk-python`
and `anthropics/claude-code-action` is accepted, so the restriction is specific to this repo):

**Branch:** https://github.com/N4darae/claude-code/tree/N4darae/settings-deny-unused-tools
**Commit:** https://github.com/N4darae/claude-code/commit/0a21cc7

```diff
diff --git a/examples/settings/README.md b/examples/settings/README.md
index 34e60ca..dc778ec 100644
--- a/examples/settings/README.md
+++ b/examples/settings/README.md
@@ -10,21 +10,23 @@ These may be applied at any level of the [settings hierarchy](https://code.claud
> [!WARNING]
> These examples are community-maintained snippets which may be unsupported or incorrect. You are responsible for the correctness of your own settings configuration.

-| Setting | [`settings-lax.json`](./settings-lax.json) | [`settings-strict.json`](./settings-strict.json) | [`settings-bash-sandbox.json`](./settings-bash-sandbox.json) |
-|---------|:---:|:---:|:---:|
-| Disable `--dangerously-skip-permissions` | ✅ | ✅ | |
-| Block plugin marketplaces | ✅ | ✅ | |
-| Block user and project-defined permission `allow` / `ask` / `deny` | | ✅ | ✅ |
-| Block user and project-defined hooks | | ✅ | |
-| Deny web fetch and search tools | | ✅ | |
-| Bash tool requires approval | | ✅ | |
-| Bash tool must run inside of sandbox | | | ✅ |
+| Setting | [`settings-lax.json`](./settings-lax.json) | [`settings-strict.json`](./settings-strict.json) | [`settings-bash-sandbox.json`](./settings-bash-sandbox.json) | [`settings-deny-unused-tools.json`](./settings-deny-unused-tools.json) |
+|---------|:---:|:---:|:---:|:---:|
+| Disable `--dangerously-skip-permissions` | ✅ | ✅ | | |
+| Block plugin marketplaces | ✅ | ✅ | | |
+| Block user and project-defined permission `allow` / `ask` / `deny` | | ✅ | ✅ | |
+| Block user and project-defined hooks | | ✅ | | |
+| Deny web fetch and search tools | | ✅ | | |
+| Bash tool requires approval | | ✅ | | |
+| Bash tool must run inside of sandbox | | | ✅ | |
+| Deny unused opt-in tools to reclaim context | | | | ✅ |

## Tips
- Consider merging snippets of the above examples to reach your desired configuration
- Settings files must be valid JSON
- Before deploying configuration files to your organization, test them locally by applying to `managed-settings.json`, `settings.json` or `settings.local.json`
- The `sandbox` property only applies to the `Bash` tool; it does not apply to other tools (like Read, Write, WebSearch, WebFetch, MCPs), hooks, or internal commands
+- `permissions.deny` on a built-in tool keeps that tool's schema out of the context window, not just the tool out of reach. Denying opt-in tools your organization does not use therefore reclaims context on every request: `settings-deny-unused-tools.json` denies `Workflow`, `ScheduleWakeup`, `ReportFindings`, `SendFeedback` and `ShareOnboardingGuide`, reclaiming 10,886 input tokens per request (-47%) in a headless measurement, of which `Workflow` alone is 7,900. The saving is reproducible; the absolute totals are not, since they also carry your `CLAUDE.md`, memory files and MCP tool definitions

## Deploying via MDM

diff --git a/examples/settings/settings-deny-unused-tools.json b/examples/settings/settings-deny-unused-tools.json
new file mode 100644
index 0000000..85acef8
--- /dev/null
+++ b/examples/settings/settings-deny-unused-tools.json
@@ -0,0 +1,11 @@
+{
+ "permissions": {
+ "deny": [
+ "Workflow",
+ "ScheduleWakeup",
+ "ReportFindings",
+ "SendFeedback",
+ "ShareOnboardingGuide"
+ ]
+ }
+}
```

Verified: the shipped file reproduces 12,166 exactly, and the session still completes
normally. Measured in headless (`-p`) mode, whose tool set is not identical to an
interactive session's - `Artifact`, `AskUserQuestion` and `SendFeedback` are absent there,
so this measurement cannot price them.

### Impact

Medium - Makes feature difficult to understand

### Additional Context

Related bug filed as #90059: `disallowedTools` in `settings.json` does not trim schemas
while the identically-named CLI flag `--disallowedTools` does. This example therefore uses
`permissions.deny`, which does trim.

Start with examples/settings/README.md and compare the existing settings examples, then inspect the proposed settings-deny-unused-tools.json contents. Done means the new example is represented in the table, its purpose and measured caveat are documented in Tips, and the JSON remains valid.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.