[DOCS] Plan mode docs omit `/plan open` and existing-plan reuse behavior

Documentation Type

Missing documentation (feature not documented)

Documentation Location

https://code.claude.com/docs/en/commands

Section/Topic

/plan command reference and the workflow for reopening or continuing an existing plan

Current Documentation

The docs currently say:

/plan [description] — "Enter plan mode directly from the prompt. Pass an optional description to enter plan mode and immediately start with that task, for example /plan fix the auth bug"

"Enter plan mode by pressing Shift+Tab or prefixing a single prompt with /plan."

plansDirectory — "Customize where plan files are stored. Path is relative to project root. Default: ~/.claude/plans"

plans/ — "Plan files written during plan mode"

No page under https://code.claude.com/docs/en/ currently documents /plan open or explains how entering plan mode should behave when an existing plan file is already present.

What's Wrong or Missing?

Changelog v2.1.119 includes this entry:

Fixed /plan and /plan open not acting on the existing plan when entering plan mode

That reveals a user-facing workflow the docs do not currently explain:

A. /plan open is undocumented

The command reference documents /plan, but not /plan open.

B. Existing-plan behavior is undocumented

The docs explain how to enter plan mode and where plan files are stored, but they do not explain that Claude Code can reopen or continue working against an existing plan when you enter plan mode again.

Users who see saved plan files, customize plansDirectory, or encounter /plan open have no documentation telling them how this workflow is supposed to work.

Suggested Improvement

Add a short plan-resume subsection to the command and plan mode docs that covers:

1. /plan open syntax and purpose
2. What /plan does when a relevant existing plan already exists
3. How this interacts with plansDirectory / ~/.claude/plans
4. Any selection rules or prompts Claude Code uses when multiple saved plans are available

At minimum, the /plan command reference should mention that Claude Code can act on an existing plan, and /plan open should appear anywhere other slash commands are documented.

Impact

Medium - Makes feature difficult to understand

Additional Context

Affected Pages:

| Page | Line(s) | Context |
|------|---------|---------|
| https://code.claude.com/docs/en/commands | 63 | Documents /plan [description], but /plan open is absent |
| https://code.claude.com/docs/en/permission-modes | 127-147 | Explains how to enter and exit plan mode, but not how existing plans are reopened or reused |
| https://code.claude.com/docs/en/settings | 207 | Documents plansDirectory without explaining how users reopen a saved plan from that directory |
| https://code.claude.com/docs/en/claude-directory | 1471-1477 | Mentions ~/.claude/plans/ as plan storage, but not the user workflow for opening those plans |

Total scope: 4 pages affected

Source: Changelog v2.1.119

Exact changelog entry:

Fixed /plan and /plan open not acting on the existing plan when entering plan mode