MCP serverio.datadef/mcp

When: Use after the final layout, where one arrow should stand for a bundle of identical flows (zone to zone). Draw one large labelled arrow SHAPE between two areas of the diagram

When: Use to record which source columns produce which target columns. No line is drawn. Record column-level lineage: which source column produces which target column, and how. Th

When: Use to add components (tables, pipelines, sources, consumers, service icons), each placed in its zone with `group`. Add one or more nodes to the canvas. Batch every node you

When: Use after the final layout to mark nodes that belong together without moving them into a zone. Regions do not move with layout. Draw a labelled translucent area behind exist

When: Use rarely: a pointer or highlight the user asked for. Never as a backdrop; zones are the containers. Place a rectangle, circle, arrow, or line as a visual annotation — a di

When: Use only when the user wants a node at a specific position, outside the automatic layout. Otherwise use canvas_add_nodes. Add a single data node at an exact position, withou

When: Use for a note that tells the diagram's reader a decision, constraint or gotcha. Pass `anchor` (the node or zone it explains) and it is placed beside it, no coordinates neede

When: Use only when the user asked for alignment that layout does not give. Align nodes to a shared edge or centre line, or space them evenly. Cleaner and far more reliable than c

When: use whenever you would otherwise make several canvas_* write calls in a row, above all with tools that take one item per call: create every zone (group_nodes), convert many n

When: Use to merge several similar nodes into one while keeping their connections, usually after canvas_suggest_simplifications. Merge several nodes into one summary node, keeping

When: Use to draw the flows that genuinely move data between two nodes. Never connect a zone: connect a node inside it. Draw edges (arrows) between nodes to show how data flows. L

When: Use when you want a flat list of every node, edge and zone. canvas_view shows the same ids as a zone tree with positions and defects, and is usually the better first read. G

When: Use to delete specific edges between two nodes. Remove edges, given as source and target, or as an edge id / "Source -> Target" string in `edge`. Batch: `edges` takes a lis

When: Use to create a zone (a layer, domain, stage or boundary), nested with `parentGroup`, optionally moving existing nodes into it: the zone is drawn around them where they are,

When: Use before changing a node's fields or columns, to see everything it carries: columns, metadata, owners, neighbours. Get full detail for specific nodes: all columns with typ

When: Use once, after the structure (zones, nodes, edges) is complete, not after each change. With no arguments it only places what was added or changed; nothing else moves. Set mo

When: Use only for a precise manual placement the user asked for: exact x/y/width/height per node. To check a layout, canvas_view is faster and already reports overlaps. Get exact

When: Use only when the user asked for a specific placement. Moving a zone moves its children; never move the children as well. Set node positions precisely. Use absolute x/y to p

When: Use to move existing nodes or zones into another zone (they are placed inside it and the zone grows to fit), or out of every zone with group null. A zone cannot move into its

When: Use to delete lineage rows between two nodes (one column pair, or all rows between them). Lineage pointing at deleted nodes or columns is cleaned automatically. Delete linea

When: Use to delete nodes and their edges. Removing a zone keeps its contents (they move up to the parent, same place on screen): that is how to ungroup. Pass keepChildren:false on

When: Use when one component changes identity or type (Redshift becomes Snowflake, a card becomes a service icon). The node keeps its id, connections, lineage, zone, position and f

When: Use only when the user asked for a specific size. Set the width and height of nodes. Mostly for shapes, text boxes, and group zones — data nodes size themselves from their c

When: Use before adding nodes that should show a vendor logo (Snowflake, Kafka, Power BI) and you are unsure of the icon id. Find icon ids in Datadef's library (2000+ cloud and da

When: Use `mode: "merge"` to add or update (renameTo) a few columns, `mode: "remove"` to drop some, or the default replace for the full list. Columns that stay keep their ids and l

When: Use when the diagram feels dense or the user asks to simplify. It changes nothing; it reports what could collapse. Report where this canvas could be collapsed — groups of si

When: Use to relabel, retype, restyle (dashed, colour), reverse, put arrowheads on both ends, or re-point an existing edge, instead of disconnecting and reconnecting it. Change ex

When: Use for any in-place change: rename a node or zone (it keeps its size and contents), edit a note's text, recolour (`color: "green"`, `fill`, `family`), change a zone's style,

When: Use before you finish: broken references and icons, nodes outside their zone, overlapping zones or nodes. Loops are reported as information only. Check your work: broken ref

When: use to see a diagram before you edit it and after each round of changes; this is how you check your work. It answers in milliseconds from the saved diagram, where export_diag

When: use when you will build the diagram yourself with the canvas_* tools, because you want control over the result or already know the architecture from the conversation. Use cre

When: use when Datadef's own model should design a whole new diagram from a description or a pasted schema. To build it yourself step by step, use create_blank_diagram; to change a

When: use for a large change you can describe in words better than you can make it tool by tool: "reorganise this into bronze, silver and gold", "rebuild the consumption side from

When: use to give the user an image of a diagram, or a link to download, attach or embed one. Not to check your own edits: a render starts a browser (6-10 s), while canvas_view ans

When: read once before your first canvas_* call, to build or to edit. Datadef's standard for a readable diagram (size, edge discipline, nested zones, notes) and the tool workflow:

When: use to show the user a diagram (it attaches a rendered PNG and a markdown image line, 6-10 s), or to poll a diagram that create_diagram or edit_diagram is still working on. T

When: use to find the id of an existing diagram before viewing, editing or exporting it. Lists the diagrams in the user's Datadef account, most recently updated first. Next: canva

Re-sync a repo-linked diagram from the current state of its repository. If the tracked branch or tag has not moved since the last sync, nothing changes. If it has, the diagram is R

For a diagram that was created from a connected git repository: which repo and branch or tag it tracks, when it last synced, the commit it reflects, and whether daily sync is on. U