Verification Report

The English locale should behave as a first-class locale for supported content and as unavailable for unsupported books.

Expected Behavior

/en renders the English home page.
/en lists only English-localized handbooks.
/en/books/claude-code-advanced renders English content.
/en/books/claude-code-command-master renders English content.
/en/books/codex-advanced does not fall back to Korean content.
The preview chapter API receives a locale parameter.
Sitemap generation includes English URLs only for English pages.

Local Checks

Run the focused handbook checks after changing locale routing or content availability:

yarn workspace handbook typecheck
yarn workspace handbook lint
yarn workspace handbook build
yarn workspace handbook test:e2e

If an E2E test fails, inspect whether it is asserting Korean-only copy or a route that is now locale-specific.

Content Checks

Every English page has English frontmatter.
Internal links use /en/books/....
Korean-only books are not registered in content/books/en/meta.json; translated books are.
The home catalog uses localized availability from the MDX source.
Language links appear only when the same page exists in more than one locale.
Claude Code content uses the 2026-08-03 check baseline: v2.1.220 (latest) and v2.1.212 (stable) from npm dist-tags, plus the official changelog through v2.1.220. npm next also points to v2.1.220.
The August 3 re-check found no newer stable release and no slash-command addition, removal, or rename.
The v2.1.206~v2.1.220 refresh covers Opus 5, the /fork and /subtask split, session/concurrency/depth limits for subagents, strict network allowlisting, optional filesystem isolation, DirectoryAdded, headless MCP validation errors, and nested subagent stream forwarding.
The v2.1.181~v2.1.205 refresh covers Sonnet 5, org default model labeling, sandbox credentials, destructive-command sandbox auto-approval, Windows PowerShell sandbox fixes, MCP login/logout, MCP idle timeout, model restrictions, deprecated-model warnings, nested-agent/background stability, Korean paste handling, and non-interactive fallback fixes. v2.1.198–201 add background-by-default subagents, Claude in Chrome GA, the /dataviz skill, the default permission mode "Manual" (v2.1.200), and removal of the mid-conversation system role on Sonnet 5 sessions (v2.1.201).
v2.1.202–205 add advisory workflow sizing and OTel attributes, the fast single-pass /review split, MCP root updates, background/Agent View reliability, headless hook streaming, the full /doctor checkup and /checkup alias, Auto-mode transcript protection, and JSON Schema fixes.
The v2.1.170 content remains valid for Fable 5 and Agent View, while the current Opus alias and default high-capability path move to Opus 5 in v2.1.219. Historical Opus 4.8 guidance is retained only where a version pin or compatibility path is explicit.
Background sessions, dynamic workflows, and the command surface were rechecked against current docs.
Fable-specific details include 30-day data retention, ZDR unavailability, always-on adaptive thinking, DISABLE_PROMPT_CACHING_FABLE, classifier fallback, and availability fallback chains.
Fable 5 redeployment: suspended 2026-06-12 under US export controls, restored globally 2026-07-01 with an improved safety classifier; plan usage is up to 50% of weekly limits through 2026-07-07 then usage credits. Mythos 5 (no classifiers) is Project Glasswing invitation-only and not selectable via /model.
Recent operating notes include /cd session relocation, --safe-mode, bundled skill/workflow disabling, self-hosted runner post-session hooks, and the v2.1.170 transcript persistence fix.

Source Baseline

Claude Code Changelog: https://code.claude.com/docs/en/changelog
Model configuration: https://code.claude.com/docs/en/model-config
Commands: https://code.claude.com/docs/en/commands
Subagents: https://code.claude.com/docs/en/sub-agents
Hooks: https://code.claude.com/docs/en/hooks
Sandboxing: https://code.claude.com/docs/en/sandboxing
Agent View: https://code.claude.com/docs/en/agent-view
Sonnet 5 announcement: https://www.anthropic.com/news/claude-sonnet-5
Claude Fable 5 and Claude Mythos 5: https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5
Fable 5 redeployment statement: https://www.anthropic.com/news/redeploying-fable-5
Claude models overview: https://platform.claude.com/docs/en/about-claude/models/overview
Opus 4.8 announcement: https://www.anthropic.com/news/claude-opus-4-8
npm package: https://www.npmjs.com/package/@anthropic-ai/claude-code

Residual Risk

The English locale now has multiple localized handbooks. Shared pages such as About and Graph have English UI labels, but deeper editorial polish should be handled as a separate content pass.

The English locale should behave as a first-class locale for supported content and as unavailable for unsupported books.

Expected Behavior

/en renders the English home page.
/en lists only English-localized handbooks.
/en/books/claude-code-advanced renders English content.
/en/books/claude-code-command-master renders English content.
/en/books/codex-advanced does not fall back to Korean content.
The preview chapter API receives a locale parameter.
Sitemap generation includes English URLs only for English pages.

Local Checks

Run the focused handbook checks after changing locale routing or content availability:

yarn workspace handbook typecheck
yarn workspace handbook lint
yarn workspace handbook build
yarn workspace handbook test:e2e

If an E2E test fails, inspect whether it is asserting Korean-only copy or a route that is now locale-specific.

Content Checks

Every English page has English frontmatter.
Internal links use /en/books/....
Korean-only books are not registered in content/books/en/meta.json; translated books are.
The home catalog uses localized availability from the MDX source.
Language links appear only when the same page exists in more than one locale.
Claude Code content uses the 2026-08-03 check baseline: v2.1.220 (latest) and v2.1.212 (stable) from npm dist-tags, plus the official changelog through v2.1.220. npm next also points to v2.1.220.
The August 3 re-check found no newer stable release and no slash-command addition, removal, or rename.
The v2.1.206~v2.1.220 refresh covers Opus 5, the /fork and /subtask split, session/concurrency/depth limits for subagents, strict network allowlisting, optional filesystem isolation, DirectoryAdded, headless MCP validation errors, and nested subagent stream forwarding.
The v2.1.181~v2.1.205 refresh covers Sonnet 5, org default model labeling, sandbox credentials, destructive-command sandbox auto-approval, Windows PowerShell sandbox fixes, MCP login/logout, MCP idle timeout, model restrictions, deprecated-model warnings, nested-agent/background stability, Korean paste handling, and non-interactive fallback fixes. v2.1.198–201 add background-by-default subagents, Claude in Chrome GA, the /dataviz skill, the default permission mode "Manual" (v2.1.200), and removal of the mid-conversation system role on Sonnet 5 sessions (v2.1.201).
v2.1.202–205 add advisory workflow sizing and OTel attributes, the fast single-pass /review split, MCP root updates, background/Agent View reliability, headless hook streaming, the full /doctor checkup and /checkup alias, Auto-mode transcript protection, and JSON Schema fixes.
The v2.1.170 content remains valid for Fable 5 and Agent View, while the current Opus alias and default high-capability path move to Opus 5 in v2.1.219. Historical Opus 4.8 guidance is retained only where a version pin or compatibility path is explicit.
Background sessions, dynamic workflows, and the command surface were rechecked against current docs.
Fable-specific details include 30-day data retention, ZDR unavailability, always-on adaptive thinking, DISABLE_PROMPT_CACHING_FABLE, classifier fallback, and availability fallback chains.
Fable 5 redeployment: suspended 2026-06-12 under US export controls, restored globally 2026-07-01 with an improved safety classifier; plan usage is up to 50% of weekly limits through 2026-07-07 then usage credits. Mythos 5 (no classifiers) is Project Glasswing invitation-only and not selectable via /model.
Recent operating notes include /cd session relocation, --safe-mode, bundled skill/workflow disabling, self-hosted runner post-session hooks, and the v2.1.170 transcript persistence fix.

Source Baseline

Claude Code Changelog: https://code.claude.com/docs/en/changelog
Model configuration: https://code.claude.com/docs/en/model-config
Commands: https://code.claude.com/docs/en/commands
Subagents: https://code.claude.com/docs/en/sub-agents
Hooks: https://code.claude.com/docs/en/hooks
Sandboxing: https://code.claude.com/docs/en/sandboxing
Agent View: https://code.claude.com/docs/en/agent-view
Sonnet 5 announcement: https://www.anthropic.com/news/claude-sonnet-5
Claude Fable 5 and Claude Mythos 5: https://platform.claude.com/docs/en/about-claude/models/introducing-claude-fable-5-and-claude-mythos-5
Fable 5 redeployment statement: https://www.anthropic.com/news/redeploying-fable-5
Claude models overview: https://platform.claude.com/docs/en/about-claude/models/overview
Opus 4.8 announcement: https://www.anthropic.com/news/claude-opus-4-8
npm package: https://www.npmjs.com/package/@anthropic-ai/claude-code

Residual Risk

The English locale now has multiple localized handbooks. Shared pages such as About and Graph have English UI labels, but deeper editorial polish should be handled as a separate content pass.

Expected Behavior

Local Checks

Content Checks

Source Baseline

Residual Risk

On this page

Verification Report

Expected Behavior

Local Checks

Content Checks

Source Baseline

Residual Risk

On this page