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+# Result Grouping UI Plan
+
+## Goal
+Allow users to combine compatible benchmark runs after import, including ScenarioBench runs performed in separate batches, without changing the original imported run metadata.
+
+## Requirements
+- Group only runs owned by the same user.
+- Require matching visibility, model, quant, confirmed GPU, GPU count, engine/build, server configuration, harness/version/mode, and thinking-level profile.
+- Preserve each run's imported label and provenance.
+- Use the explicit group as the dashboard/session identity.
+- Allow users to remove a run from a group later.
+
+## ScenarioBench Rules
+- Combine selected ScenarioBench runs into one aggregate row.
+- Preview all scenarios before confirmation.
+- Reject duplicate scenario identities by default.
+- When a duplicate exists, require the user to select the retained attempt.
+- Do not silently count multiple attempts as separate benchmark scenarios.
+
+## Regular Suite Rules
+- Preview included suites, task counts, thinking levels, pass/fail totals, and duplicate task identities.
+- Merge disjoint task batches normally.
+- Warn about overlapping tasks and require an explicit decision before grouping.
+
+## Data Model
+1. Add `result_groups`:
+   - owner/user ID
+   - display name
+   - compatibility fingerprint
+   - visibility
+   - timestamps
+2. Add `result_group_runs`:
+   - result group ID
+   - benchmark run ID
+   - unique membership constraint
+3. Keep grouping metadata separate from immutable `benchmark_runs` provenance.
+
+## Summary Generation
+1. Update `festbench:summary`:
+   - Group runs assigned to a result group by group ID.
+   - Keep existing metadata-plus-label grouping for ungrouped runs.
+2. Display the group name as the session label.
+3. Aggregate ScenarioBench only after duplicate-scenario validation.
+
+## User Interface
+1. Add selection controls to **My Runs**.
+2. Add actions:
+   - Create result group
+   - Add to existing result group
+   - Remove from result group
+3. Show only compatible groups as destinations.
+4. Add a confirmation modal with:
+   - Matching metadata
+   - Included runs and suites
+   - Scenario/task overlap warnings
+   - Aggregate pass/fail preview
+5. Rebuild session summaries and the home snapshot after any group membership change.
+
+## Validation and Authorization
+- Enforce ownership on every group and membership operation.
+- Block incompatible metadata by default.
+- Block duplicate ScenarioBench scenarios by default.
+- Block groups crossing visibility boundaries.
+- Block grouping runs with different engine builds or server configurations.
+
+## Tests
+1. Two disjoint ScenarioBench batches form one aggregate.
+2. Duplicate ScenarioBench scenarios are rejected.
+3. Incompatible model, quant, GPU/count, engine/build, config, visibility, harness, or thinking level are rejected.
+4. Removing a run restores its ordinary standalone grouping.
+5. Users cannot group runs they do not own.
+6. Existing label-based grouping remains unchanged for ungrouped runs.
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