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+# Navigation Mode Feature Plan
+
+## Concept
+A custom navigation mode where keypresses are automatically prefixed with `[` or `]`, making it easier to navigate using Neovim's bracket-based navigation pairs without repeatedly typing brackets.
+
+## User Experience
+
+### Entry
+- `z[` - Enter navigation mode with `[` prefix active (backward)
+- `z]` - Enter navigation mode with `]` prefix active (forward)
+
+### In Mode
+- All letter keys (`a-z`, `A-Z`) get prefixed with current bracket
+- Examples:
+  - Press `c` → executes `[c` or `]c` (git hunks)
+  - Press `d` → executes `[d` or `]d` (diagnostics)
+  - Press `m` → executes `[m` or `]m` (methods)
+  - Press `f` → executes `[f` or `]f` (functions)
+  - Press `b` → executes `[b` or `]b` (buffers)
+  - Press `q` → executes `[q` or `]q` (quickfix)
+
+### Toggle Prefix
+- `[` - Switch to `[` prefix (backward navigation)
+- `]` - Switch to `]` prefix (forward navigation)
+
+### Exit
+- `<Esc>` - Exit navigation mode and restore normal mappings
+
+## Technical Implementation
+
+### State Management
+```lua
+local NavMode = {
+  active = false,
+  prefix = '[',  -- '[' or ']'
+}
+```
+
+### Key Remapping Strategy
+1. Store original mappings for letters a-z, A-Z
+2. On mode entry, create new mappings: `key → prefix .. key`
+3. On mode exit, restore original mappings
+4. On prefix toggle, update all mappings with new prefix
+
+### Keys to Remap
+- Lowercase: `a-z` (26 keys)
+- Uppercase: `A-Z` (26 keys)
+- Total: 52 keys dynamically remapped
+
+### Common Bracket Navigation Pairs
+- `[c`/`]c` - Previous/next git hunk (gitsigns)
+- `[d`/`]d` - Previous/next diagnostic
+- `[b`/`]b` - Previous/next buffer (custom mapping)
+- `[q`/`]q` - Previous/next quickfix item
+- `[l`/`]l` - Previous/next location list item
+- `[m`/`]m` - Previous/next method (treesitter textobjects)
+- `[f`/`]f` - Previous/next function (treesitter textobjects)
+- `[p`/`]p` - Previous/next parameter (treesitter textobjects)
+- `[t`/`]t` - Previous/next tag
+
+## Implementation Details
+
+### Module Structure
+Create `lua/navigation-mode.lua`:
+
+```lua
+local M = {}
+
+local state = {
+  active = false,
+  prefix = '[',
+  stored_mappings = {},
+}
+
+local LETTERS = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
+
+function M.enter(prefix)
+  if state.active then return end
+  
+  state.prefix = prefix or '['
+  state.active = true
+  
+  -- Store original mappings and create prefixed ones
+  for i = 1, #LETTERS do
+    local key = LETTERS:sub(i, i)
+    -- Store original mapping (if exists)
+    -- Create new mapping: key → prefix .. key
+    vim.keymap.set('n', key, state.prefix .. key, { noremap = true, silent = true })
+  end
+  
+  -- Special mappings for [ and ] to toggle prefix
+  vim.keymap.set('n', '[', function() M.set_prefix('[') end, { noremap = true, silent = true })
+  vim.keymap.set('n', ']', function() M.set_prefix(']') end, { noremap = true, silent = true })
+  
+  -- Exit mapping
+  vim.keymap.set('n', '<Esc>', function() M.exit() end, { noremap = true, silent = true })
+  
+  -- TODO: Set visual feedback (statusline, notification, etc.)
+end
+
+function M.set_prefix(new_prefix)
+  if not state.active then return end
+  state.prefix = new_prefix
+  
+  -- Remap all letters with new prefix
+  for i = 1, #LETTERS do
+    local key = LETTERS:sub(i, i)
+    vim.keymap.set('n', key, state.prefix .. key, { noremap = true, silent = true })
+  end
+  
+  -- TODO: Update visual feedback
+end
+
+function M.exit()
+  if not state.active then return end
+  
+  -- Restore original mappings
+  for i = 1, #LETTERS do
+    local key = LETTERS:sub(i, i)
+    vim.keymap.del('n', key)
+    -- Restore stored mapping if it existed
+  end
+  
+  -- Clean up special mappings
+  vim.keymap.del('n', '[')
+  vim.keymap.del('n', ']')
+  vim.keymap.del('n', '<Esc>')
+  
+  state.active = false
+  
+  -- TODO: Clear visual feedback
+end
+
+return M
+```
+
+### Integration in keymaps.lua
+```lua
+-- Navigation mode
+vim.keymap.set('n', 'z[', function()
+  require('navigation-mode').enter('[')
+end, { desc = 'Enter navigation mode (backward)' })
+
+vim.keymap.set('n', 'z]', function()
+  require('navigation-mode').enter(']')
+end, { desc = 'Enter navigation mode (forward)' })
+```
+
+## Visual Feedback Options (TODO)
+
+Need to decide on one or more:
+
+1. **Statusline indicator**: Show `[NAV ←]` or `[NAV →]` in statusline
+2. **Notification**: Brief message on mode entry/exit
+3. **Command line**: `echo` message showing current prefix
+4. **Cursor highlight**: Change cursor color/shape
+5. **Virtual text**: Floating indicator in corner of window
+
+## Open Questions
+
+1. **Mapping conflicts**: How to handle if a letter already has a mapping?
+   - Overwrite temporarily?
+   - Skip that letter?
+   - Warn user?
+
+2. **Buffer-local mappings**: Should mode respect buffer-local mappings?
+   - Store and restore per-buffer?
+   - Global mode only?
+
+3. **Visual feedback**: Which approach is clearest without being intrusive?
+
+4. **Number keys**: Should `0-9` also be prefixed?
+   - Useful for some navigation pairs
+   - But might conflict with counts
+
+5. **Operators**: Should `d`, `c`, `y` still work as operators or only as navigation?
+   - Current plan: They become navigation only while in mode
+   - Trade-off: Can't delete/change while navigating
+
+## Implementation Phases
+
+1. **Core functionality** (essential)
+   - Mode enter/exit
+   - Key remapping for a-z
+   - Prefix toggle
+   - Basic state management
+
+2. **Visual feedback** (important)
+   - Choose and implement feedback mechanism
+   - Ensure clarity when mode is active
+
+3. **Edge cases** (polish)
+   - Handle existing mappings gracefully
+   - Buffer-local mapping preservation
+   - Mode timeout/auto-exit?
+
+4. **Documentation** (completion)
+   - Update README.md with keymaps
+   - Add examples of useful navigation pairs
+   - Consider adding to help docs
+
+## Estimated Complexity
+- **Core**: ~100-150 lines of Lua
+- **Visual feedback**: +20-50 lines depending on approach
+- **Edge case handling**: +30-50 lines
+- **Total**: 150-250 lines
+
+## Testing Checklist
+- [ ] Enter mode with `z[` and `z]`
+- [ ] Verify letter keys are prefixed correctly
+- [ ] Toggle between `[` and `]` prefix
+- [ ] Exit cleanly with `<Esc>`
+- [ ] No residual mappings after exit
+- [ ] Works across different buffers
+- [ ] Visual feedback is clear
+- [ ] Common navigation pairs work (c, d, m, f, q)