# Tasks — Agent Robustness Optimization

## Priority 1: Configuration Foundation

- [x] 1. Add new config fields to AppConfig
  - [x] 1.1 Add `max_data_context_retries` field (default=2) with `APP_MAX_DATA_CONTEXT_RETRIES` env override to `config/app_config.py`
  - [x] 1.2 Add `conversation_window_size` field (default=10) with `APP_CONVERSATION_WINDOW_SIZE` env override to `config/app_config.py`
  - [x] 1.3 Add `max_parallel_profiles` field (default=4) with `APP_MAX_PARALLEL_PROFILES` env override to `config/app_config.py`

## Priority 2: Data Privacy Fallback (R1–R3)

- [ ] 2. Implement error classification
  - [-] 2.1 Add `_classify_error(error_message: str) -> str` method to `DataAnalysisAgent` in `data_analysis_agent.py` with regex patterns for KeyError, ValueError, NameError, empty DataFrame
  - [-] 2.2 Add `_extract_column_from_error(error_message: str) -> Optional[str]` function to `utils/data_privacy.py`
  - [-] 2.3 Add `_lookup_column_in_profile(column_name, safe_profile) -> Optional[dict]` function to `utils/data_privacy.py`
- [ ] 3. Implement enriched hint generation
  - [-] 3.1 Add `generate_enriched_hint(error_message: str, safe_profile: str) -> str` function to `utils/data_privacy.py`
  - [-] 3.2 Integrate retry logic into the `analyze()` loop in `data_analysis_agent.py`: add per-round retry counter, call `_classify_error` on failures, generate enriched hint when below retry limit, fall back to normal error handling at limit

## Priority 3: Conversation History Trimming (R4–R5)

- [ ] 4. Implement conversation trimming
  - [~] 4.1 Add `_trim_conversation_history()` method to `DataAnalysisAgent` implementing sliding window with first-message preservation
  - [~] 4.2 Add `_compress_trimmed_messages(messages: list) -> str` method to `DataAnalysisAgent` that generates summary with action types and success/failure, excluding code blocks and raw output
  - [~] 4.3 Call `_trim_conversation_history()` at the start of each round in the `analyze()` loop, after the first round

## Priority 4: Analysis Template System (R6–R8)

- [ ] 5. Backend template integration
  - [~] 5.1 Add optional `template_name` parameter to `DataAnalysisAgent.analyze()` method; retrieve template via `get_template()`, prepend `get_full_prompt()` to user requirement
  - [~] 5.2 Add `GET /api/templates` endpoint to `web/main.py` returning `list_templates()` result
  - [~] 5.3 Add optional `template` field to `StartRequest` model in `web/main.py`; pass template name to agent in `run_analysis_task`
- [ ] 6. Frontend template selector
  - [~] 6.1 Add template selector HTML section (cards above requirement input) to `web/static/index.html`
  - [~] 6.2 Add template fetching, selection logic, and "No Template" default to `web/static/script.js`
  - [~] 6.3 Add template card styles (`.template-card`, `.template-card.selected`) to `web/static/clean_style.css`

## Priority 5: Frontend Progress Bar (R9)

- [ ] 7. Backend progress updates
  - [~] 7.1 Add `set_progress_callback(callback)` method to `DataAnalysisAgent`; call callback at start of each round in `analyze()` loop
  - [~] 7.2 Wire progress callback in `run_analysis_task` in `web/main.py` to update `SessionData` progress fields
  - [~] 7.3 Add `current_round`, `max_rounds`, `progress_percentage`, `status_message` to `GET /api/status` response in `web/main.py`
- [ ] 8. Frontend progress bar
  - [~] 8.1 Add progress bar HTML element below the status bar area in `web/static/index.html`
  - [~] 8.2 Add `updateProgressBar(percentage, message)` function to `web/static/script.js`; call it during polling when `is_running` is true; set to 100% on completion
  - [~] 8.3 Add progress bar styles with CSS transition animation to `web/static/clean_style.css`

## Priority 6: Multi-File Chunked & Parallel Loading (R10–R11)

- [ ] 9. Chunked loading enhancement
  - [~] 9.1 Add `_profile_chunked(file_path: str) -> str` function to `utils/data_loader.py` that profiles using first chunk + sampled subsequent chunks
  - [~] 9.2 Add `load_and_profile_data_smart(file_paths, max_file_size_mb) -> str` function to `utils/data_loader.py` that selects chunked vs full loading based on file size threshold
  - [~] 9.3 Update `DataAnalysisAgent.analyze()` to use smart loader and expose chunked iterator in Code_Executor namespace for large files
- [ ] 10. Parallel profiling
  - [~] 10.1 Add `_profile_files_parallel(file_paths: list) -> tuple[str, str]` method to `DataAnalysisAgent` using `ThreadPoolExecutor` with `max_parallel_profiles` workers
  - [~] 10.2 Update `DataAnalysisAgent.analyze()` to call `_profile_files_parallel` when multiple files are provided, replacing sequential `build_safe_profile` + `build_local_profile` calls

## Priority 7: Testing

- [ ] 11. Write property-based tests
  - [ ] 11.1 ~PBT~ Property test for error classification correctness (Property 1) using `hypothesis`
  - [ ] 11.2 ~PBT~ Property test for enriched hint content and privacy (Property 3) using `hypothesis`
  - [ ] 11.3 ~PBT~ Property test for env var config override (Property 4) using `hypothesis`
  - [ ] 11.4 ~PBT~ Property test for sliding window trimming invariants (Property 5) using `hypothesis`
  - [ ] 11.5 ~PBT~ Property test for trimming summary content (Property 6) using `hypothesis`
  - [ ] 11.6 ~PBT~ Property test for template prompt integration (Property 7) using `hypothesis`
  - [ ] 11.7 ~PBT~ Property test for invalid template error (Property 8) using `hypothesis`
  - [ ] 11.8 ~PBT~ Property test for parallel profile merge with error resilience (Property 11) using `hypothesis`
- [ ] 12. Write unit and integration tests
  - [ ] 12.1 Unit tests for error classifier with known error messages
  - [ ] 12.2 Unit tests for conversation trimming at boundary conditions
  - [ ] 12.3 Integration tests for `GET /api/templates` and `POST /api/start` with template field
  - [ ] 12.4 Integration tests for `GET /api/status` progress fields