Add /clear command to clear goose context (#1802)

Co-authored-by: Bradley Axen <baxen@squareup.com>

crates/goose-cli/src/session/input.rs

@@ -17,6 +17,7 @@ pub enum InputResult {
     GooseMode(String),
     Plan(PlanCommandOptions),
     EndPlan,
+    Clear,
     Recipe(Option<String>),
     Summarize,
 }
@@ -91,6 +92,7 @@ fn handle_slash_command(input: &str) -> Option<InputResult> {
     const CMD_MODE: &str = "/mode ";
     const CMD_PLAN: &str = "/plan";
     const CMD_ENDPLAN: &str = "/endplan";
+    const CMD_CLEAR: &str = "/clear";
     const CMD_RECIPE: &str = "/recipe";
     const CMD_SUMMARIZE: &str = "/summarize";
 
@@ -134,6 +136,7 @@ fn handle_slash_command(input: &str) -> Option<InputResult> {
         }
         s if s.starts_with(CMD_PLAN) => parse_plan_command(s[CMD_PLAN.len()..].trim().to_string()),
         s if s == CMD_ENDPLAN => Some(InputResult::EndPlan),
+        s if s == CMD_CLEAR => Some(InputResult::Clear),
         s if s.starts_with(CMD_RECIPE) => parse_recipe_command(s),
         s if s == CMD_SUMMARIZE => Some(InputResult::Summarize),
         _ => None,
@@ -246,6 +249,7 @@ fn print_help() {
                        If no filepath is provided, it will be saved to ./recipe.yaml.
 /summarize - Summarize the current conversation to reduce context length while preserving key information.
 /? or /help - Display this help message
+/clear - Clears the current chat history
 
 Navigation:
 Ctrl+C - Interrupt goose (resets the interaction to before the interrupted user request)

crates/goose-cli/src/session/mod.rs

@@ -521,6 +521,17 @@ impl Session {
                     output::render_exit_plan_mode();
                     continue;
                 }
+                input::InputResult::Clear => {
+                    save_history(&mut editor);
+
+                    self.messages.clear();
+                    tracing::info!("Chat context cleared by user.");
+                    output::render_message(
+                        &Message::assistant().with_text("Chat context cleared."),
+                        self.debug,
+                    );
+                    continue;
+                }
                 input::InputResult::PromptCommand(opts) => {
                     save_history(&mut editor);
                     self.handle_prompt_command(opts).await?;