docs: cli newline keybinding (#6823)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

documentation/docs/guides/environment-variables.md

@@ -158,6 +158,7 @@ These variables control how goose manages conversation sessions and context.
 | `GOOSE_SUBAGENT_MAX_TURNS` | Sets the maximum turns allowed for a [subagent](/docs/guides/subagents) to complete before timeout | Integer (e.g., 25) | 25 |
 | `CONTEXT_FILE_NAMES` | Specifies custom filenames for [hint/context files](/docs/guides/context-engineering/using-goosehints#custom-context-files) | JSON array of strings (e.g., `["CLAUDE.md", ".goosehints"]`) | `[".goosehints"]` |
 | `GOOSE_CLI_THEME` | [Theme](/docs/guides/goose-cli-commands#themes) for CLI response  markdown | "light", "dark", "ansi" | "dark" |
+| `GOOSE_CLI_NEWLINE_KEY` | Customize the keyboard shortcut for [inserting newlines in CLI input](/docs/guides/goose-cli-commands#keyboard-shortcuts) | Single character (e.g., "n", "m") | "j" (Ctrl+J) |
 | `GOOSE_RANDOM_THINKING_MESSAGES` | Controls whether to show amusing random messages during processing | "true", "false" | "true" |
 | `GOOSE_CLI_SHOW_COST` | Toggles display of model cost estimates in CLI output | "true", "1" (case insensitive) to enable | false |
 | `GOOSE_AUTO_COMPACT_THRESHOLD` | Set the percentage threshold at which goose [automatically summarizes your session](/docs/guides/sessions/smart-context-management#automatic-compaction). | Float between 0.0 and 1.0 (disabled at 0.0) | 0.8 |
@@ -189,6 +190,9 @@ export CONTEXT_FILE_NAMES='["CLAUDE.md", ".goosehints", ".cursorrules", "project
 # Set the ANSI theme for the session
 export GOOSE_CLI_THEME=ansi
 
+# Use Ctrl+N instead of Ctrl+J for newline
+export GOOSE_CLI_NEWLINE_KEY=n
+
 # Disable random thinking messages for less distraction
 export GOOSE_RANDOM_THINKING_MESSAGES=false
 

documentation/docs/guides/goose-cli-commands.md

@@ -731,8 +731,8 @@ goose session --name use-custom-theme
 ### Keyboard Shortcuts
 
 **Session Control:**
-- **`Ctrl+C`** - Interrupt the current request
-- **`Ctrl+J`** - Add a newline
+- **`Ctrl+C`** - Clear the current line if text is entered, interrupt the current request if processing, or exit the session if line is empty
+- **`Ctrl+J`** - Add a newline. Can customize the character via `GOOSE_CLI_NEWLINE_KEY` in the [config file](/docs/guides/config-files) (e.g. `GOOSE_CLI_NEWLINE_KEY: n`) or as an [environment variable](/docs/guides/environment-variables#session-management). Avoid "c" and common terminal shortcuts like "r", "w", "z".
 
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