Function insert_reminders

crates/opencode-session/src/prompt.rs:3027–3071

(
    messages: &[SessionMessage],
    agent_name: &str,
    was_plan: bool,
)

- Report progress to the user"#;

pub fn insert_reminders(
    messages: &[SessionMessage],
    agent_name: &str,
    was_plan: bool,
) -> Vec<SessionMessage> {
    let last_user_idx = messages
        .iter()
        .rposition(|m| matches!(m.role, MessageRole::User));

    if let Some(idx) = last_user_idx {
        let mut messages = messages.to_vec();

        if agent_name == "plan" {
            let reminder_text = PROMPT_PLAN.to_string();
            messages[idx].parts.push(crate::MessagePart {
                id: format!("prt_{}", uuid::Uuid::new_v4()),
                part_type: PartType::Text {
                    text: reminder_text,
                    synthetic: None,
                    ignored: None,
                },
                created_at: chrono::Utc::now(),
                message_id: None,
            });
        }

        if was_plan && agent_name == "build" {
            let reminder_text = BUILD_SWITCH.to_string();
            messages[idx].parts.push(crate::MessagePart {
                id: format!("prt_{}", uuid::Uuid::new_v4()),
                part_type: PartType::Text {
                    text: reminder_text,
                    synthetic: None,
                    ignored: None,
                },
                created_at: chrono::Utc::now(),
                message_id: None,
            });
        }

        messages
    } else {
        messages.to_vec()
    }
}

pub fn was_plan_agent(messages: &[SessionMessage]) -> bool {
    messages.iter().any(|m| {