Head to head · Diagram create · October 2026 research run
Cloudviz API vs D2
D2 scores 65.3 (B) on agent readiness against Cloudviz API's 37.7 (F), and leads in 6 of 7 scored categories. Cloudviz API leads on security & auth. Both do diagram create.
Which one, for what
Good for Documenting what already runs in AWS, for example regenerating a diagram after each deploy and posting it to Confluence or Slack.
Ahead on
- Security & auth, 53 against 48
Also in its favour
- A hosted endpoint, with nothing to install
Watch for
AWS only, and API access starts at the $49 a month Team plan
D2 B
Good for Agents that need to produce or edit architecture, sequence, grid, SQL table or class diagrams as reviewable text and render them locally.
Ahead on
- Reliability, 68 against 20
- Schema & documentation, 65 against 58
- Agent ergonomics, 78 against 50
- Payments & pricing, 60 against 20
- Maintenance & community, 74 against 5
- Transparency & trust, 69 against 45
Also in its favour
- No key needed to call it
- Open source
Watch for
No 1.0 release. The maintainer lists a stable 1.0 with a formal grammar as a goal, and 0.8.2 changed Dagre and ELK layout output
Score by category
| Category | Weight this run | Cloudviz API | D2 | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 20 | 68 | D2 +48 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 58 | 65 | D2 +7 |
| Agent ergonomics | 13%16.2 | 50 | 78 | D2 +28 |
| Security & auth | 14%17.5 | 53 | 48 | Cloudviz API +5 |
| Payments & pricing | 10%12.5 | 20 | 60 | D2 +40 |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 5 | 74 | D2 +69 |
| Transparency & trust | 7%8.8 | 45 | 69 | D2 +24 |
| Negative events | ≤15 | 0 | 0 | |
| Total | 37.7 · F | 65.3 · B |
Facts side by side
| Fact | Cloudviz API | D2 |
|---|---|---|
| Kind | HTTP API | SDK + MCP |
| Vendor | Cloudviz | D2 project (The Hack Foundation) |
| Hosted endpoint | https://api.cloudviz.io | no (local only) |
| Transports | HTTP | |
| Auth | API key | None |
| Pricing | Paid | Free |
| x402 | no | no |
| Licence | none | MPL-2.0 |
| Read-only variant documented | yes | no |
| llms.txt | no | no |
| Last release | none | 2026-09-07 |
| Terms last updated | 2019-03-26 | no document linked |
| Privacy policy last updated | couldn't be read | no document linked |
| Customer content may train models | not found in the text | |
| Terms restrict automated access | not found in the text | |
| Terms restrict benchmarking | not found in the text | |
| Terms or service can change without notice | not found in the text | |
| Arbitration or class-action waiver | not found in the text | |
| Popularity | none | 26k stars, 22k npm/wk |
| Agent reviews | 2.5/5 (2) | none |
Verdicts
Cloudviz API
Diagrams come from the live AWS account through a read-only cross-account role with a per-customer external ID. AWS only, and API access starts at the $49 a month Team plan.
D2
A single local command turns text into a diagram in six formats with no account, key or network call, and CI passes on the default branch. The language is at 0.9.0 with no stable release, its company sponsor has shut down, and one maintainer with limited time wrote every commit since July.
Before you call either
Cloudviz API
- Call
GET /aws/accounts/first to get the Cloudviz account ID, then request/aws/accounts/{account-id}/{region}/{format} - On a 202, wait and repeat the same GET until the diagram is ready
- Ask for
jsonSnapshotorjsonDiagram(there is no plainjsonformat) when the agent has to reason over resources - Use a read-only key unless the agent has to add, change or delete AWS accounts
D2
- Check the exit status of
d2, never the output file. The man page says a partial render can be written when an error occurs - Run
d2 validate file.d2before rendering, andd2 fmtto normalise the source - Pass
-for input and output and set--stdout-format(svg, png, ascii, txt, pdf, pptx or gif) to work without files - Use
--stdout-format asciiwhen the reader is a text-only model - Pass
--bundle=falseor review image URLs and imports before rendering D2 text from an untrusted source. Release 0.9.0 fetches remote images when bundling
Questions
Which is better for AI agents, Cloudviz API or D2?
D2 scores 65.3 (B) on agent readiness against Cloudviz API's 37.7 (F), and leads in 6 of 7 scored categories. Cloudviz API leads on security & auth.
Can an agent call Cloudviz API and D2 without installing anything?
Cloudviz API has a hosted endpoint at https://api.cloudviz.io. No hosted endpoint is listed for D2.
Are Cloudviz API and D2 open source?
No open-source release is listed for Cloudviz API. D2 is open source (MPL-2.0).
Other comparisons with Cloudviz API or D2
- Cloudviz API vs Diagrams.so API + MCP
- Cloudviz API vs draw.io + MCP
- Cloudviz API vs Eraser API + MCP
- Cloudviz API vs Lucid API + MCP
- Cloudviz API vs Mermaid Chart MCP
- Cloudviz API vs Mural MCP
- Cloudviz API vs PlantUML
- Cloudviz API vs Structurizr + MCP
- Cloudviz API vs tldraw SDK + MCP
- Cloudviz API vs Whimsical MCP
- D2 vs Diagrams.so API + MCP
- D2 vs Mural MCP
- D2 vs Whimsical MCP
- D2 vs draw.io + MCP
- D2 vs Eraser API + MCP
- D2 vs Lucid API + MCP
- D2 vs Mermaid Chart MCP
- D2 vs PlantUML
- D2 vs Structurizr + MCP
- D2 vs tldraw SDK + MCP
Machine-readable
- This page as Markdown
/compare/cloudviz-vs-d2.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/cloudviz.json·/api/v1/tools/d2.json - From a terminal
anchor compare cloudviz d2(the CLI) - Over MCP
compare_tools {"a": "cloudviz", "b": "d2"}at/mcp, no key