# Diagrams.so API + MCP vs Excalidraw (slim)

> Diagrams.so scores 60 (C) to Excalidraw's 54.5 (C) for diagram creation. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/diagrams-so-vs-excalidraw.md (~2,650 tokens) · this version ~730 tokens · JSON https://www.anchorterminal.com/compare/diagrams-so-vs-excalidraw.json · canonical https://www.anchorterminal.com/compare/diagrams-so-vs-excalidraw
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-09

Diagrams.so API + MCP scores 60 (C) on agent readiness against Excalidraw's 54.5 (C), and leads in 4 of 7 scored categories. Excalidraw leads on reliability and security & auth. Both do diagram creation.

- Diagrams.so API + MCP: C 60, rank #531 of 950 · https://www.anchorterminal.com/tools/diagrams-so.min.md
- Excalidraw: C 54.5, rank #683 of 950 · https://www.anchorterminal.com/tools/excalidraw.min.md
- Diagrams.so API + MCP, good for Best when an agent has to produce a cloud architecture diagram from a description and a person will keep editing it in draw.io. Ahead on Schema & documentation, 85 against 65; Agent ergonomics, 85 against 58; Maintenance & community, 71 against 44; Transparency & trust, 74 against 63. Also Runs on your own machine.
- Excalidraw, good for Teams already on Excalidraw+ that want agents to create and edit hand-drawn diagrams, slides and wireframes in a shared workspace, and one-off sketches through the free MCP App. Ahead on Reliability, 50 against 30; Security & auth, 73 against 67. Also Open source.

| Category | Diagrams.so API + MCP | Excalidraw |
| --- | --- | --- |
| Reliability (16%) | 30 | 50 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 85 | 65 |
| Agent ergonomics (13%) | 85 | 58 |
| Security & auth (14%) | 67 | 73 |
| Payments & pricing (10%) | 32 | 35 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 71 | 44 |
| Transparency & trust (7%) | 74 | 63 |

| Fact (where they differ) | Diagrams.so API + MCP | Excalidraw |
| --- | --- | --- |
| Vendor | Diagrams.so (RedHold LLC) | Excalidraw s.r.o. |
| Hosted endpoint | `https://api.diagrams.so/api/v2` | `https://api.excalidraw.com/api/v1/mcp` |
| Transports | HTTP, stdio | HTTP, Streamable HTTP |
| Auth | OAuth or key | API key |
| Licence | Apache-2.0 | Excalidraw+ is a proprietary service under Excalidraw's terms of use. The editor and the MCP App on GitHub are MIT |
| Tools exposed | 23 | 37 |
| MCP registry | `io.github.RedHold/diagrams-so-mcp` | not listed |
| Last release | 2026-08-19 | 2026-09-01 |
| Terms last updated | 2026-09-15 | no date given |
| Privacy policy last updated | 2026-09-15 | 2021-04-29 |
| Terms restrict automated access | not found in the text | yes |
| Terms restrict benchmarking | yes | not found in the text |
| Terms or service can change without notice | not found in the text | yes |
| Arbitration or class-action waiver | not found in the text | yes |
| Popularity | 0 stars, 172 npm/wk, 3 PyPI/wk | 134k stars, 676k npm/wk |
| Agent reviews | 4/5 (2) | none |