1# Phase 4: Plan Documentation Impact
 2
 3You are determining whether and how documentation should be updated based on code changes.
 4
 5## Objective
 6Produce a structured documentation plan that will guide Phase 5 execution.
 7
 8## Documentation System
 9This is an **mdBook** site (https://rust-lang.github.io/mdBook/):
10- `docs/src/SUMMARY.md` defines book structure per https://rust-lang.github.io/mdBook/format/summary.html
11- If adding new pages, they MUST be added to SUMMARY.md
12- Use `{#kb action::ActionName}` syntax for keybindings (custom preprocessor expands these)
13- Prettier formatting (80 char width) will be applied automatically
14
15## Input
16You will receive:
17- Change analysis from Phase 3
18- Repository structure from Phase 2
19- Documentation guidelines from `docs/AGENTS.md`
20
21## Instructions
22
231. **Review AGENTS.md**
24   - Load and apply all rules from `docs/AGENTS.md`
25   - Respect scope boundaries (in-scope vs out-of-scope)
26
272. **Evaluate Documentation Impact**
28   For each behavioral change from Phase 3:
29   - Does existing documentation cover this area?
30   - Is the documentation now inaccurate or incomplete?
31   - Classify per AGENTS.md "Change Classification" section
32
333. **Identify Specific Updates**
34   For each required update:
35   - Exact file path
36   - Specific section or heading
37   - Type of change (update existing, add new, deprecate)
38   - Description of the change
39
404. **Flag Uncertainty**
41   Explicitly mark:
42   - Assumptions you're making
43   - Areas where human confirmation is needed
44   - Ambiguous requirements
45
465. **Output Format**
47Use the exact format specified in `docs/AGENTS.md` Phase 4 section:
48
49```markdown
50## Documentation Impact Assessment
51
52### Summary
53Brief description of code changes analyzed.
54
55### Documentation Updates Required: [Yes/No]
56
57### Planned Changes
58
59#### 1. [File Path]
60- **Section**: [Section name or "New section"]
61- **Change Type**: [Update/Add/Deprecate]
62- **Reason**: Why this change is needed
63- **Description**: What will be added/modified
64
65### Uncertainty Flags
66- [ ] [Description of any assumptions or areas needing confirmation]
67
68### No Changes Needed
69- [List files reviewed but not requiring updates, with brief reason]
70```
71
72## Constraints
73- Read-only: Do not modify any files
74- Conservative: When uncertain, flag for human review rather than planning changes
75- Scoped: Only plan changes that trace directly to code changes from Phase 3
76- No scope expansion: Do not plan "improvements" unrelated to triggering changes