# Parameter :: 2. `case_sensitive::`
Enable case-sensitive matching in search operations.
**Type:** Boolean
**Fundamental Type:** Boolean flag
**Constraints:**
- Valid values: `0`, `1`
- `0` = case-insensitive (default)
- `1` = case-sensitive
**Default:** `0` (case-insensitive)
**Commands:** `.search`
**Purpose:** Controls whether search matches are case-sensitive. Default case-insensitive mode is practical for most searches; enable case-sensitive when searching for identifiers, variable names, or other case-significant strings.
**Examples:**
```bash
# Valid values
case_sensitive::0 # Case-insensitive (default)
case_sensitive::1 # Case-sensitive
# Invalid values
case_sensitive::true # Not a boolean: "case_sensitive must be 0 or 1"
```
### Referenced Type
| Boolean | Base type | Boolean flag | `0` (false) or `1` (true) |
### Referenced Commands
| 5 | [`.search`](../command/05_search.md) | `0` | Enables case-sensitive matching |
### Referenced User Stories
| 2 | [Find Past Conversation](../user_story/002_find_past_conversation.md) | developer |