Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/itsjool/d2-mcp/d2npx skills add ItsJooL/d2-mcp --skill d2git clone --depth 1 https://github.com/ItsJooL/d2-mcpWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00068 | $0.07064 |
| Opus 5 | $0.00034 | $0.03532 |
| Sonnet 5 | $0.00014 | $0.01413 |
| Haiku 4.5 | $0.00007 | $0.00706 |
Grade A, and why
d2 scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 930 lines — stays where its author put it; the contents beside it link to each section on GitHub.
D2 Diagram Language
D2 is a declarative diagram scripting language that compiles to SVG. Text → diagrams. Docs: https://d2lang.com | Playground: https://play.d2lang.com
Diagram Type Selection
Choose the right diagram type before writing any code:
| User wants to show... | Use this D2 pattern |
|---|---|
| System components and how they connect | Containers + connections (architecture) |
| Request/response flow, API interactions, message order | shape: sequence_diagram |
| A process, algorithm, or decision tree | Shapes + directed connections (flowchart) |
| Database tables and foreign keys | shape: sql_table (ER diagram) |
| Class hierarchies, object relationships | shape: class (UML class diagram) |
| System context: users, systems, boundaries (C4) | Containers + shape: c4-person + theme 303 |
| A state machine or lifecycle | Shapes + labeled connections (state diagram) |
| Progressive reveal / storytelling | steps: {} with animate_interval |
| Multiple views of the same system | layers: {} or scenarios: {} |
| A dashboard / grid of metrics | Container with grid-rows / grid-columns |
Default shape: rectangle. Use direction: right or direction: down to control flow.
Workflow: Responding to a Diagram Request
-
Pick the diagram type (use the table above)
-
Draft the D2 code — start with core entities, add connections, add style last
-
Call
d2_inspect, then draw an ASCII replica from its output:d2_inspect(d2_code=...)Use the inspect output to hand-draw a clean ASCII diagram using box-drawing characters (
┌─┐│└┘├┤┬┴┼ ▶ ◀ ↓ ↑). You are generating this ASCII — not the D2 renderer. This avoids all of D2's known ASCII rendering bugs (cross-container connections, reverse edges, direction:right).How to draw it:
- Containers become labelled boxes:
┌─ Control Plane ──────┐ - Child shapes are indented inside their parent box
- Connections are drawn as arrows between boxes with their labels
- Cross-container connections are shown as arrows spanning between the boxes
- Use
→for forward,←for reverse,↔for bidirectional,--for undirected - For sequence diagrams: draw actors as columns with arrows between them
- For steps/layers: show each board as a separate section
- Containers become labelled boxes:
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- yesterday First seen · 930 lines · 68 tokens per session scan A a6e5588b7d1c
d2 is a skill published in the GitHub repository ItsJooL/d2-mcp (0 stars, last pushed 4mo ago), licensed MIT. It adds 68 tokens to every session and 7,064 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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brainstorming
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auto-perf-optimize
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chat-perf
Run chat perf benchmarks and memory leak checks against the local dev build or any published VS Code version. Use when investigating chat rendering regressions, validating perf-sensitive changes to chat UI, or checking for memory leaks in the chat response pipeline.
chat-pet-sprite-creation
Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.
cpu-profile-analysis
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