Claude Code 2.1.175 - what changed

What's new

[new] Added projects tool with project_info, project_read, project_search, project_write, and project_delete methods for managing project-scoped knowledge and docs.
[new] Added support for the claude-opus-4-8 model ID.
[changed] Refined high-severity action intent rules to require specific user-provided parameters rather than inferred ones.
[changed] Updated focus mode behavior so only the final text message is shown when enabled.
[changed] Adjusted context management and tool rejection messaging for clarity when a request is interrupted or denied.

Models & prompts

Opus 4.8 is now referenced in fallback guidance and safety classifier notes.
Added instructions clarifying that the project is optional and should only be used when relevant to the request.
Updated tokenizer notes to account for Opus 4.7+ token count differences and the need to re-baseline max_tokens and context budgets.
Refined server-side fallback header requirements to server-side-fallback-2026-06-01.

Under the hood

New environment variables: CLAUDE_CODE_ENABLE_REMOTE_RECAP, CLAUDE_CODE_HIDE_SETTINGS_HINT, CLAUDE_OPUS_4_8, CLAUDE_PROJECT_TOOL, CLAUDE_PROJECT_UUID, CLAUDE_STAGE_FILE_ROOT, and the CLAUDE_STAGE group.
Several internal Statsig feature gates were added or retired, including gates related to tool retry handling, plugin autoupdate, and Opus 4.6 sunset.

Upgrade notes

Projects created or written with the new tool are namespaced under claude/<name> when a bare filename is supplied.

What's new

[new] Added projects tool with project_info, project_read, project_search, project_write, and project_delete methods for managing project-scoped knowledge and docs.

[new] Added support for the claude-opus-4-8 model ID.

[changed] Refined high-severity action intent rules to require specific user-provided parameters rather than inferred ones.

[changed] Updated focus mode behavior so only the final text message is shown when enabled.

[changed] Adjusted context management and tool rejection messaging for clarity when a request is interrupted or denied.

Models & prompts

Opus 4.8 is now referenced in fallback guidance and safety classifier notes.

Added instructions clarifying that the project is optional and should only be used when relevant to the request.

Updated tokenizer notes to account for Opus 4.7+ token count differences and the need to re-baseline max_tokens and context budgets.

Refined server-side fallback header requirements to server-side-fallback-2026-06-01.

Under the hood

New environment variables: CLAUDE_CODE_ENABLE_REMOTE_RECAP, CLAUDE_CODE_HIDE_SETTINGS_HINT, CLAUDE_OPUS_4_8, CLAUDE_PROJECT_TOOL, CLAUDE_PROJECT_UUID, CLAUDE_STAGE_FILE_ROOT, and the CLAUDE_STAGE group.

Several internal Statsig feature gates were added or retired, including gates related to tool retry handling, plugin autoupdate, and Opus 4.6 sunset.