Method load_conversation_history

src-tauri/src/agents/runner.rs:482–576

Load conversation history from DB with smart context management: - Sliding window: max 20 recent message pairs - Strip html:preview blocks from assistant outputs (saves ~5-10KB per widget) - Token budget: ~8K tokens max for history (~32K chars) - Smarter truncation: user messages 500 chars, assistant 1500 chars

(
        &self,
        session_id: &str,
    )

    /// - Token budget: ~8K tokens max for history (~32K chars)
    /// - Smarter truncation: user messages 500 chars, assistant 1500 chars
    async fn load_conversation_history(
        &self,
        session_id: &str,
    ) -> AppResult<Vec<ConversationMessage>> {
        const MAX_HISTORY_PAIRS: usize = 20;
        const MAX_TOTAL_CHARS: usize = 32_000; // ~8K tokens
        const MAX_USER_MSG_CHARS: usize = 500;
        const MAX_ASSISTANT_MSG_CHARS: usize = 1500;

        // Load user messages
        let user_messages = sqlx::query_as::<_, crate::models::Message>(
            "SELECT id, session_id, role, content, created_at FROM messages \
             WHERE session_id = ?1 ORDER BY created_at ASC",
        )
        .bind(session_id)
        .fetch_all(&self.db)
        .await?;

        // Load completed top-level agent runs (not subagents)
        let agent_runs = sqlx::query_as::<_, crate::models::AgentRun>(
            "SELECT id, session_id, agent_type, status, input, output, error, started_at, completed_at, created_at, parent_agent_run_id, project_path \
             FROM agent_runs \
             WHERE session_id = ?1 AND parent_agent_run_id IS NULL AND status = 'completed' AND output IS NOT NULL \
             ORDER BY created_at ASC",
        )
        .bind(session_id)
        .fetch_all(&self.db)
        .await?;

        // Interleave chronologically
        let mut history: Vec<(String, String, String)> = Vec::new();

        for msg in &user_messages {
            history.push((msg.created_at.clone(), msg.role.clone(), msg.content.clone()));
        }

        for run in &agent_runs {
            if let Some(output) = &run.output {
                let created = run.completed_at.as_deref().unwrap_or(&run.created_at);
                history.push((created.to_string(), "assistant".to_string(), output.clone()));
            }
        }

        history.sort_by(|a, b| a.0.cmp(&b.0));

        // Sliding window: take only the most recent N pairs
        let window_start = if history.len() > MAX_HISTORY_PAIRS * 2 {
            history.len() - MAX_HISTORY_PAIRS * 2
        } else {
            0
        };
        let windowed = &history[window_start..];

        // Convert to ConversationMessages with smart truncation + token budget
        let mut conversation: Vec<ConversationMessage> = Vec::new();
        let mut total_chars: usize = 0;

        for (_, role, content) in windowed {