[FEATURE] Claude Code CLI can detect timezone

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Problem Statement

Claude cannot accurately display calendar event times or determine "current time"
relative to the user because system timezone is not included in the environment
context.

Impact

• Affected Use Cases: Calendar/scheduling MCP tools, time-based queries, travel

scenarios

• User Experience: Incorrect meeting times displayed, especially during DST

transitions

Proposed Solution

Current Behavior

Environment block includes: working directory, git status, platform, shell, OS
version
Environment block does not include: timezone

Desired Behavior

Add timezone to <env> block:
Timezone: America/Los_Angeles (PDT, UTC-7)

User Benefits

1. Accurate meeting time display across DST transitions
2. Correct filtering of "upcoming" or "remaining" events
3. Automatic timezone detection when users travel
4. No manual CLAUDE.md configuration needed

Implementation Notes

Detection methods:

• macOS/Linux: date +%Z or read /etc/localtime
• Windows: System timezone settings

Format suggestion: {IANA_timezone} ({abbreviation}, UTC{offset})
Example: America/Los_Angeles (PDT, UTC-7)

Alternative Solutions

Workaround

Users can manually document timezone in CLAUDE.md, but this doesn't handle DST or
travel automatically.

Priority

Medium - Would be very helpful

Feature Category

Configuration and settings

Use Case Example

Using MCP to use calendar as source for problem solving. Claude gets the times of events wrong because it doesn't know my timezone. I could save it manually, but as soon as I go on a business trip, Claude gets event times wrong.

Additional Context

_No response_