> ## Documentation Index > Fetch the complete documentation index at: https://docs.bedrock.cv/llms.txt > Use this file to discover all available pages before exploring further. # Revision Comparison > Compare drawing revisions and inspect changes. ## User Prompt > "Compare the latest arch set with the previous revision and show me what changed." ## Tool Call Sequence **Call:** `Query` ```json theme={null} { "entity": "sheet", "project_id": "proj_oak", "discipline": "A", "search": "arch" } ``` **Response:** ```json theme={null} { "count": 12, "items": [ { "id": "sh_a101_b", "sheet_number": "A-101", "title": "FIRST FLOOR PLAN", "discipline": "A", "drawing": { "id": "dr_arch_b", "name": "Arch Set Rev B" }, "uri": "storage://sheets/sh_a101_b/image.png", "blocks": [ { "id": "blk_a101_plan_b", "type": "Plan", "identifier": "1", "name": "FIRST FLOOR PLAN", "description": "...", "uri": "...", "relations": [ { "relation_type": "similar_to", "target": { "entity_type": "block", "id": "blk_a101_plan_a", "type": "Plan", "sheet_number": "A-101", "drawing_name": "Arch Set Rev A" } } ]} ] }, { "id": "sh_a101_a", "sheet_number": "A-101", "title": "FIRST FLOOR PLAN", "discipline": "A", "drawing": { "id": "dr_arch_a", "name": "Arch Set Rev A" }, "uri": "storage://sheets/sh_a101_a/image.png", "blocks": [ "..." ] } ] } ``` **What the agent learns:** There are two architectural drawings -- "Arch Set Rev A" (`dr_arch_a`) and "Arch Set Rev B" (`dr_arch_b`). The agent identifies these as the two revisions to compare. **Call:** `Compare` ```json theme={null} { "project_id": "proj_oak", "drawing_a_id": "dr_arch_a", "drawing_b_id": "dr_arch_b" } ``` **Response:** ```json theme={null} { "job_id": "job_cmp_01", "status": "queued" } ``` **What the agent learns:** The comparison job is queued. The agent needs to poll for completion. **Call:** `PollJob` ```json theme={null} { "job_id": "job_cmp_01" } ``` **Response:** ```json theme={null} { "id": "job_cmp_01", "status": "completed", "progress": { "completed": 8, "total": 8 }, "result": { "overlays": [ { "id": "ov_01", "block_a": { "type": "Plan", "sheet_number": "A-101", "drawing_name": "Arch Set Rev A" }, "block_b": { "type": "Plan", "sheet_number": "A-101", "drawing_name": "Arch Set Rev B" }, "score": 0.82, "uri": "storage://overlays/ov_01/composite.png" }, { "id": "ov_02", "block_a": { "type": "Plan", "sheet_number": "A-102", "drawing_name": "Arch Set Rev A" }, "block_b": { "type": "Plan", "sheet_number": "A-102", "drawing_name": "Arch Set Rev B" }, "score": 0.97, "uri": "storage://overlays/ov_02/composite.png" } ] } } ``` **What the agent learns:** 8 sheet pairs were compared. A-101 has a score of 0.82 (significant changes), while A-102 has 0.97 (minimal changes). The agent focuses on A-101 first. **Call:** `Query` ```json theme={null} { "entity": "block", "project_id": "proj_oak", "id": "blk_a101_plan_b", "include": ["overlays", "changes"] } ``` **Response:** ```json theme={null} { "count": 1, "items": [ { "id": "blk_a101_plan_b", "type": "Plan", "identifier": "1", "name": "FIRST FLOOR PLAN", "uri": "storage://blocks/blk_a101_plan_b/image.png", "confidence": 0.96, "sheet": { "id": "sh_a101_b", "sheet_number": "A-101", "discipline": "A" }, "drawing": { "id": "dr_arch_b", "name": "Arch Set Rev B" }, "relations": [], "overlays": [ { "id": "ov_01", "score": 0.82, "uri": "storage://overlays/ov_01/composite.png", "addition_uri": "storage://overlays/ov_01/additions.png", "deletion_uri": "storage://overlays/ov_01/deletions.png", "paired_block": { "id": "blk_a101_plan_a", "type": "Plan", "sheet_number": "A-101", "drawing_name": "Arch Set Rev A" }, "changes": [ { "description": "New wall added between Room 102 and 103 at grid B-3", "bounds": { "xmin": 380, "ymin": 500, "xmax": 420, "ymax": 650 } }, { "description": "Door 104 relocated from south wall to east wall of Room 102", "bounds": { "xmin": 300, "ymin": 540, "xmax": 350, "ymax": 590 } }, { "description": "Room 103 label changed from STORAGE to IT CLOSET", "bounds": { "xmin": 400, "ymin": 550, "xmax": 450, "ymax": 580 } } ] } ] } ] } ``` **What the agent learns:** Three specific changes on A-101: a new wall, a relocated door, and a renamed room. Each has a bounding box for spatial context. **Call:** `ViewImage` ```json theme={null} { "uri": "storage://overlays/ov_01/composite.png" } ``` **Response:** ```json theme={null} { "url": "https://cdn.bedrock.cv/signed/ov_01.png?token=...", "expires_in": 900 } ``` **What the agent learns:** The overlay image is ready to display to the user. ## Agent Response > I compared **Arch Set Rev A** with **Arch Set Rev B** across 8 sheet pairs. Here are the results: > > **A-101 (First Floor Plan)** had the most changes (score: 0.82): > > 1. **New wall** added between Room 102 and 103 at grid B-3 > > 2. **Door 104** relocated from south wall to east wall of Room 102 > > 3. **Room 103** renamed from STORAGE to IT CLOSET > > **A-102 (Second Floor Plan)** had minimal changes (score: 0.97). > > Would you like me to drill into any specific change or check the other sheets? ## Summary | Metric | Value | | ------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Tool calls | **5** | | Tools used | `Query` (sheet) > `Compare` > `PollJob` > `Query` (block) > `ViewImage` | | Key technique | The agent sorts overlays by score to prioritize sheets with the most changes. The async `Compare` > `PollJob` pattern lets the agent report progress while processing runs. |