Viewer Tabs
When you open a Blueprint function in NodeLens, the viewer shows it in multiple formats through a set of tabs. Each tab gives a different perspective on the same graph — from human-readable pseudocode to compact formats designed for AI input.
Tab Overview
| Tab | Best for |
|---|---|
| Canvas | Visual inspection of the graph — nodes, wires, pin connections |
| Pseudocode | Understanding the logic in plain language — closest to how you'd describe it in words |
| BSL | Compact read format for AI orientation — shows execution flow with node IDs for surgical edits |
| BGL | Read-write format — used by AI to generate and modify Blueprint graphs |
| Exec Tree | Linear execution trace — shows the order nodes fire, with inline data |
| IR | Intermediate representation — structured, language-neutral form of the logic |
| Mermaid | Flowchart diagram source — paste into any Mermaid renderer to get a visual diagram |
| Graph JSON | Full structured data of the graph — used internally and for advanced AI context |
Pseudocode
The Pseudocode tab renders the Blueprint function as readable pseudocode — structured like real code but without language-specific syntax. It shows the execution flow, conditions, loops, variable assignments, and function calls in a format that anyone familiar with programming can follow.
This is the best starting point when you want to understand what a function does at a glance, or when giving context to an AI that doesn't need the full graph structure.
BSL — Blueprint Script Language
BSL is a compact, read-oriented format designed for AI use. It shows the execution flow of the graph with each node identified by a short ID, making it easy for an AI to get oriented quickly without processing a large amount of data.
BSL is a read-only format — the AI reads it to understand the graph structure
and identify which nodes to target. Actual modifications are made using
BGL or the apply_edits tool via the MCP server.
BGL — Blueprint Graph Language
BGL is the primary format for AI-assisted Blueprint creation and editing. It is a compact text representation of the full graph — nodes, pins, connections, and default values — that an AI can both read and write.
When you ask the AI to create a new function or modify an existing one, it works in BGL. The result is then imported via the Import panel or applied automatically through the MCP server. See the BGL Format page for full documentation.
Exec Tree
The Exec Tree tab shows the execution order of the graph as a linear tree. Each node is listed in the order it fires, with branches shown as indented subtrees. Inline data — such as the target object, arguments, and return values — is shown next to each node.
This is useful for tracing exactly what happens step by step when the function runs, especially for complex graphs with multiple branches.
IR — Intermediate Representation
The IR tab shows the graph in a structured, language-neutral form. It is more precise than pseudocode and closer to the actual graph data, but still human-readable. Operators, comparisons, and function calls are expressed in a consistent format regardless of the original Blueprint node types.
Mermaid
The Mermaid tab outputs the graph as a Mermaid flowchart definition. You can copy this text and paste it into any Mermaid-compatible renderer — such as the Mermaid Live Editor, Notion, GitHub Markdown, or Obsidian — to get a visual diagram.
Graph JSON
The Graph JSON tab shows the full structured data of the Blueprint graph — every node, pin, connection, and default value in JSON format. It is available in two modes:
- Compact — abbreviated keys, only connected or non-default pins included. Smaller and faster for AI context.
- Full — all nodes and pins with complete data. Used for the Canvas and advanced inspection.
- Single Line — compact JSON on one line, for pasting into tools that don't handle multiline JSON.
Action Buttons
The viewer header contains a row of action buttons that apply to the currently open function. Some buttons are context-sensitive — they change behavior depending on which tab is active.
- + Import Opens the Import panel, where you can paste Blueprint clipboard data or BGL text, parse it, and save it as a new function. See the Import page for details.
- + Context Loads the current function into the AI chat as context. The AI will use the content of the active tab (Pseudocode, BGL, Graph JSON, etc.) as reference for the conversation. Disabled when viewing an MD file.
- Copy Copies the content of the active tab to the clipboard. Works for all text tabs — Pseudocode, BSL, BGL, Exec Tree, IR, Mermaid, and Graph JSON. Disabled on the Canvas tab. A "Copied!" toast confirms the action.
- Word Wrap Toggles word wrap on and off for text tabs. Useful for long lines in Pseudocode, Exec Tree, or IR that extend beyond the viewer width. Disabled on the Canvas tab.
- Edit Available when viewing an MD (notes) file. Switches between view mode and live edit mode. In edit mode you can write and format notes directly in the viewer. See the MD Files page for details.
- Close Closes the current function and returns to the home panel.