feat: refine CLI command and help UX

.github/workflows/live-e2e.yml

@@ -107,5 +107,4 @@ jobs:
           fi
           bin/tdc fs delete-file-system \
             --profile live-e2e \
-            --file-system-name "$TDC_LIVE_FS_NAME" \
-            --confirm-file-system-name "$TDC_LIVE_FS_NAME"
+            --file-system-name "$TDC_LIVE_FS_NAME"

.gitmodules

@@ -11,7 +11,3 @@
 	path = docs/pingcap-docs/docs
 	url = git@github.com:pingcap/docs.git
 	branch = release-8.5
-[submodule "docs/pingcap-docs/docs-cn"]
-	path = docs/pingcap-docs/docs-cn
-	url = git@github.com:pingcap/docs-cn.git
-	branch = release-8.5

AGENTS.md

@@ -51,7 +51,7 @@ Implemented:
   `docs/spec/done/0018-fs-token-auth-and-config-free-access.md`
 - install and update distribution from
   `docs/spec/done/0012-install-and-update-distribution.md`
-- English and Chinese PingCAP Preview documentation from
+- English PingCAP Preview documentation from
   `docs/spec/done/0019-pingcap-tdc-documentation.md`
 - `tdc configure`
 - `tdc update --check`
@@ -288,7 +288,6 @@ docs/priciples.md           product principles and MVP scope source of truth
 docs/spec/                  pending requirement specs
 docs/spec/done/             completed requirement specs
 docs/pingcap-docs/docs/     pingcap/docs English documentation submodule
-docs/pingcap-docs/docs-cn/  pingcap/docs-cn Chinese documentation submodule
 ref/                        read-only reference implementations
 ```
 
@@ -344,10 +343,16 @@ Follow these rules unless `docs/priciples.md` is updated:
   credential source.
 - Every command should be usable by scripts and agents without
   terminal-specific assumptions.
+- When creating a pull request, check whether the target repository has a pull
+  request template. If it does, follow that template when writing the pull
+  request description.
 - Help must work as:
   - `tdc help`
   - `tdc <command> help`
   - `tdc <command> <subcommand> help`
+- In generated Flags and Global Flags sections, render value types as
+  `<type>` and append `(required)` to flags marked with
+  `tdc_usage_required`.
 - Keep the global `--version` behavior intact at every command level. Do not
   add command-specific `--version <value>` flags; use names such as
   `--target-version` when a command needs a version input.
@@ -374,6 +379,8 @@ Follow these rules unless `docs/priciples.md` is updated:
 
 Implemented command behavior:
 
+- `tdc` without a command returns `cli.missing_command` with exit code `2` and
+  an AWS-style compact two-level usage synopsis on stderr
 - `tdc configure`
 - `tdc configure --non-interactive`
 - `tdc help`
@@ -427,8 +434,8 @@ Implemented command behavior:
 - `tdc fs create-file-system --file-system-name workspace --wait`
 - `tdc fs create-file-system --file-system-name workspace --dry-run`
 - `tdc fs create-file-system --file-system-name scratch --set-default`
-- `tdc fs delete-file-system --file-system-name workspace --confirm-file-system-name workspace`
-- `tdc fs delete-file-system --file-system-name workspace --confirm-file-system-name workspace --dry-run`
+- `tdc fs delete-file-system --file-system-name workspace`
+- `tdc fs delete-file-system --file-system-name workspace --dry-run`
 - `tdc fs list-file-systems`
 - `tdc fs describe-file-system --file-system-name workspace`
 - `tdc fs set-default-file-system --file-system-name workspace`
@@ -595,12 +602,12 @@ Registered command surface:
 
 Do not rename commands without updating specs, README, e2e tests, and AGENTS.
 Any code change that changes user-visible behavior must keep README.md in sync.
-It must also update the matching English and Chinese tdc pages under
-`docs/pingcap-docs/` when the published behavior changes. Keep both locale
-trees structurally identical, use globally unique `tdc-` basenames, preserve
-the standard Preview note on every page, and update both `TOC-ai.md` files and
-both `ai/_index.md` pages when adding or removing a document. Validate command
-names and flags against the compiled CLI help, not historical specs or demos.
+It must also update the matching English tdc pages under
+`docs/pingcap-docs/docs/` when the published behavior changes. Use globally
+unique `tdc-` basenames, preserve the standard Preview note on every page, and
+update `TOC-ai.md` and `ai/_index.md` when adding or removing a document.
+Validate command names and flags against the compiled CLI help, not historical
+specs or demos.
 
 ## Configuration And Credentials
 

README.md

@@ -171,7 +171,7 @@ Each project includes a `type`: `tidbx` identifies a regular project and `tidbx_
 
 ## Commands
 
-Run `tdc help`, `tdc <command> help`, or `tdc <command> <subcommand> help` for flags and examples.
+Running `tdc` without a command returns a usage error and a compact two-level command synopsis. Run `tdc help`, `tdc <command> help`, or `tdc <command> <subcommand> help` for the full command list, flags, and examples. Help displays flag value types in angle brackets and marks required flags with `(required)`.
 
 <details>
 <summary>All commands</summary>
@@ -268,7 +268,6 @@ tdc update --target-version v0.1.1
 ## Documentation
 
 - [English Preview documentation](docs/pingcap-docs/docs/ai/tdc/tdc-overview.md)
-- [中文预览文档](docs/pingcap-docs/docs-cn/ai/tdc/tdc-overview.md)
 
 ## Build from source
 

cmd/tdc/main.go

@@ -17,7 +17,7 @@ func main() {
 
 	root := cli.NewRootCommand(version.Current())
 	if err := cli.Execute(ctx, root, os.Args[1:], os.Stdout, os.Stderr); err != nil {
-		fmt.Fprintf(os.Stderr, "tdc [ERROR]: %s\n", apperr.MessageFor(err))
+		fmt.Fprintf(os.Stderr, "\ntdc [ERROR]: %s\n", apperr.MessageFor(err))
 		os.Exit(apperr.ExitCodeFor(err))
 	}
 }

docs/present.md

@@ -387,8 +387,7 @@ rm -f /tmp/tdc-demo-token.txt
 
 ```bash
 bin/tdc fs delete-file-system \
-  --file-system-name tdc-demo-workspace \
-  --confirm-file-system-name tdc-demo-workspace
+  --file-system-name tdc-demo-workspace
 ```
 
 删除演示 cluster：

docs/spec/done/0001-cli-foundation.md

@@ -38,7 +38,12 @@ on.
   include component-specific version details when a component has them.
 - Unknown commands and flags must return non-zero exit codes with actionable
   errors.
+- Running `tdc` without a command returns the `cli.missing_command` usage error
+  with exit code `2` and a compact two-level command synopsis. Users can run
+  `tdc help` for the complete command and flag listing.
 - Help text must be deterministic and suitable for agents to parse.
+- Flags and Global Flags sections render value types as `<type>` and append
+  `(required)` after flags declared required by the command contract.
 
 ## Inputs And Config
 
@@ -112,7 +117,7 @@ rendering are local-only.
 - `tdc help`, root/command/subcommand `--version`, and nested help commands
   work.
 - No command exposes short flags.
-- Tests cover unknown command handling and help availability.
+- Tests cover missing and unknown command handling and help availability.
 
 ## Out Of Scope
 

docs/spec/done/0009-tdc-fs-control-plane.md

@@ -65,7 +65,7 @@ canonical region:
 tdc fs check-file-system
 tdc fs create-file-system --file-system-name workspace --dry-run
 tdc fs create-file-system --file-system-name workspace
-tdc fs delete-file-system --file-system-name workspace --confirm-file-system-name workspace
+tdc fs delete-file-system --file-system-name workspace
 ```
 
 The user chooses one canonical region code during `tdc configure`; the CLI
@@ -85,8 +85,8 @@ resolves all fs endpoints internally.
   selecting `tidb_cloud_native` entries.
 - `internal/fs/status` defines the structured check response with local config,
   credential, permission, endpoint, and service health entries.
-- Delete safety is implemented through an explicit long flag, initially
-  `--confirm-file-system-name <name>`.
+- Deletion requires an explicit `--file-system-name <name>` and does not add a
+  console-style name confirmation flag.
 
 ## API Call Chain
 
@@ -140,7 +140,7 @@ Command mapping:
      canonical `fs_region_code` in `[profile]` of `~/.tdc/config`.
   5. Store `fs_api_key` in `[profile]` of `~/.tdc/credentials`.
 - `tdc fs delete-file-system`
-  1. Validate `--confirm-file-system-name`.
+  1. Validate `--file-system-name`.
   2. Resolve the tdc fs base URL through the region manifest.
   3. Load the stored resource API key and call `DELETE /v1/tenant` with
      `Authorization: Bearer <api-key>`.

docs/spec/done/0013-github-actions-ci-cd.md

@@ -81,7 +81,7 @@ Then it runs:
 FS_NAME="tdc-live-e2e-${GITHUB_RUN_ID}-${GITHUB_RUN_ATTEMPT}"
 bin/tdc fs create-file-system --profile live-e2e --file-system-name "$FS_NAME"
 make live-e2e
-bin/tdc fs delete-file-system --profile live-e2e --file-system-name "$FS_NAME" --confirm-file-system-name "$FS_NAME"
+bin/tdc fs delete-file-system --profile live-e2e --file-system-name "$FS_NAME"
 ```
 
 The workflow must not commit or upload `~/.tdc/` as an artifact.

docs/spec/done/0016-profile-fs-resource-registry.md

@@ -101,7 +101,7 @@ New or changed commands:
 
 ```bash
 tdc fs create-file-system --file-system-name <name> [--set-default] [--wait] [--dry-run]
-tdc fs delete-file-system --file-system-name <name> --confirm-file-system-name <name> [--dry-run]
+tdc fs delete-file-system --file-system-name <name> [--dry-run]
 tdc fs list-file-systems
 tdc fs describe-file-system --file-system-name <name>
 tdc fs check-file-system [--file-system-name <name>]

docs/spec/done/0019-pingcap-tdc-documentation.md

@@ -2,9 +2,9 @@
 
 ## Goal
 
-Publish complete Preview documentation for tdc in the English and Chinese PingCAP documentation repositories. The documentation must help a new user reach a successful result quickly, cover every implemented command, explain the tdc and Drive9 ownership boundary, and provide scenario-based examples for database, filesystem, Git workspace, journal, vault, and ephemeral agent workflows.
+Publish complete Preview documentation for tdc in the English PingCAP Cloud documentation repository. The documentation must help a new user reach a successful result quickly, cover every implemented command, explain the tdc and Drive9 ownership boundary, and provide scenario-based examples for database, filesystem, Git workspace, journal, vault, and ephemeral agent workflows.
 
-The English documentation lives in the `pingcap/docs` submodule at `docs/pingcap-docs/docs/`. The Chinese translation lives in the `pingcap/docs-cn` submodule at `docs/pingcap-docs/docs-cn/`. Both submodules track the `release-8.5` branch and must keep matching document structures and links.
+The documentation lives in the `pingcap/docs` submodule at `docs/pingcap-docs/docs/`. The submodule tracks the `release-8.5` branch. TiDB Cloud documentation is not translated into `pingcap/docs-cn`.
 
 This is a documentation-only requirement. It does not add or change tdc runtime behavior, TiDB Cloud APIs, Drive9 APIs, configuration formats, credentials, commands, or dependencies.
 
@@ -22,15 +22,7 @@ English:
 > tdc is currently in Preview. Its features and command-line interface might change without prior notice.
 ```
 
-Chinese:
-
-```markdown
-> **注意：**
->
-> tdc 当前处于预览（Preview）阶段，其功能和命令行界面可能会发生变更，恕不另行通知。
-```
-
-The tdc section labels in both `TOC-ai.md` files and both AI home pages must also include `(Preview)`.
+The tdc section label in `TOC-ai.md` and the AI home page must also include `(Preview)`.
 
 Product feedback and bug reports must point to:
 
@@ -44,7 +36,7 @@ Do not direct ordinary tdc feedback to the TiDB, Drive9, or PingCAP docs issue t
 
 All new tdc Markdown basenames must be globally unique within each PingCAP documentation repository, even when files are stored in different directories. Every basename must start with the `tdc-` prefix and use the existing PingCAP docs kebab-case naming convention. Do not add a generic `_index.md`, `overview.md`, `quick-start.md`, or `reference.md` under the tdc tree.
 
-The English and Chinese repositories use the same relative paths:
+The English repository uses these relative paths:
 
 ```text
 ai/tdc/
@@ -75,7 +67,7 @@ ai/tdc/
     tdc-troubleshooting.md
 ```
 
-All internal links use absolute PingCAP documentation paths rooted at `/ai/tdc/`. English and Chinese links use the same paths; locale routing is handled by the documentation site.
+All internal links use absolute PingCAP documentation paths rooted at `/ai/tdc/`.
 
 ## Documentation Style
 
@@ -90,7 +82,7 @@ Follow the existing PingCAP documentation templates and AI documentation style:
 - Commands use the installed `tdc` name, never the local development path `bin/tdc`.
 - Examples use placeholders and synthetic resource names. Never include real API keys, FS tokens, SQL passwords, vault tokens, project IDs, cluster IDs, tenant IDs, or customer data.
 - Secrets should be passed through environment variables where possible. If a secret flag must be explained, warn that flags may remain in shell history or process listings.
-- English is the source documentation. Chinese pages preserve the same technical meaning and command blocks but use natural Chinese technical writing rather than literal machine translation.
+- English is the only published language for these TiDB Cloud pages.
 - Product and command names remain in their canonical form: `tdc`, TiDB Cloud Starter, TiDB Cloud Filesystem, `tdc fs`, `tdc fs-git`, `tdc fs-journal`, and `tdc fs-vault`.
 
 Do not document `make build`, `go build`, `go install`, or source compilation as an end-user installation method. Developers who need source builds can use the tdc GitHub repository. Published user installation documentation covers only supported release installers and updates.
@@ -267,20 +259,18 @@ Do not document pending telemetry commands or unimplemented serverless-function/
 
 ## Navigation
 
-Update both files:
+Update:
 
 ```text
 docs/pingcap-docs/docs/TOC-ai.md
-docs/pingcap-docs/docs-cn/TOC-ai.md
 ```
 
 Under Quick Start, Concepts, Guides, Examples, and Reference, add a nested `TiDB Cloud CLI (tdc) (Preview)` group with direct links to all corresponding tdc pages. Do not expose only the overview while leaving the other pages unreachable from the TOC.
 
-Update both AI home pages:
+Update the AI home page:
 
 ```text
 docs/pingcap-docs/docs/ai/_index.md
-docs/pingcap-docs/docs-cn/ai/_index.md
 ```
 
 Add a `TiDB Cloud CLI (tdc) (Preview)` section with concise grouped tables linking directly to every tdc page. `tdc-overview.md` is the tdc landing page; no generic `_index.md` is added under `ai/tdc/`.
@@ -324,12 +314,10 @@ The two documentation directories are independent Git submodules:
 
 1. Create an English docs branch from `release-8.5` in `docs/pingcap-docs/docs`.
 2. Write and validate the English pages, `TOC-ai.md`, and AI home-page updates.
-3. Create a Chinese docs branch from `release-8.5` in `docs/pingcap-docs/docs-cn`.
-4. Translate the final English structure and update the Chinese TOC and AI home page.
-5. Validate both submodule worktrees independently.
-6. Commit changes inside each submodule.
-7. Update the parent tdc repository gitlinks to the reviewed submodule commits.
-8. Update the parent tdc current docs and completed-spec annotations in the same tdc change set.
+3. Validate the documentation submodule worktree.
+4. Commit changes inside the submodule.
+5. Update the parent tdc repository gitlink to the reviewed submodule commit.
+6. Update the parent tdc current docs and completed-spec annotations in the same tdc change set.
 
 Do not make the tdc build, tests, packaging, or release artifacts depend on either documentation submodule. The submodules are documentation source only.
 
@@ -342,17 +330,16 @@ No example may depend on an undocumented endpoint, raw server URL, or direct Dri
 ## Dependencies And Platform
 
 - Depends on all completed MVP command specs through `0018`.
-- Depends on the `pingcap/docs` and `pingcap/docs-cn` submodules tracking `release-8.5`.
+- Depends on the `pingcap/docs` submodule tracking `release-8.5`.
 - Adds no Go package, cgo, runtime, installer, or service dependency.
 - Published installation instructions support release installers only.
 - Platform documentation must be based on current tested behavior and must distinguish macOS WebDAV from optional macFUSE/FUSE.
 
 ## Acceptance Criteria
 
-- Every English tdc page has a matching Chinese page at the same relative path.
 - Every new Markdown basename starts with `tdc-` and is globally unique in its repository.
 - Every page includes valid front matter and the standard Preview note.
-- Both TOC files directly link every tdc page under the correct category.
+- `TOC-ai.md` directly links every tdc page under the correct category.
 - Both AI home pages directly link every tdc page.
 - All internal links resolve to files or approved external URLs.
 - The overview links feedback to `https://github.com/tidbcloud/tdc/issues`.
@@ -365,7 +352,7 @@ No example may depend on an undocumented endpoint, raw server URL, or direct Dri
 - Examples use only synthetic values and never expose a real secret.
 - `docs/priciples.md`, `docs/present.md`, README, AGENTS, and the listed completed specs no longer present superseded behavior as current behavior.
 - Archived README snapshots and historical release notes remain unchanged.
-- English and Chinese Markdown lint and link checks pass using each documentation repository's available validation workflow.
+- English Markdown lint and link checks pass using the documentation repository's available validation workflow.
 - The parent tdc repository records clean submodule gitlinks with no uncommitted documentation changes.
 
 ## Out Of Scope