# pen.dev vs Subframe (slim)

> pen.dev scores 47.6 (D) to Subframe's 39.7 (E) for design files. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/pen-dev-vs-subframe.md (~2,300 tokens) · this version ~730 tokens · JSON https://www.anchorterminal.com/compare/pen-dev-vs-subframe.json · canonical https://www.anchorterminal.com/compare/pen-dev-vs-subframe
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-09

pen.dev scores 47.6 (D) on agent readiness against Subframe's 39.7 (E), and leads in 4 of 7 scored categories. Subframe leads on security & auth and maintenance & community. Both do design files.

- pen.dev: D 47.6, rank #832 of 950 · https://www.anchorterminal.com/tools/pen-dev.min.md
- Subframe: E 39.7, rank #915 of 950 · https://www.anchorterminal.com/tools/subframe.min.md
- pen.dev, good for A coding agent that designs screens beside the code and keeps them in Git, including in CI. Ahead on Reliability, 33 against 19; Schema & documentation, 61 against 54; Agent ergonomics, 66 against 47; Payments & pricing, 38 against 33. Also Runs on your own machine; No incidents deducted, where Subframe loses 3 points for them.
- Subframe, good for A coding agent working beside a team that designs React and Tailwind interfaces in Subframe and wants the design as code, with a read-only route for review. Ahead on Security & auth, 44 against 33; Maintenance & community, 65 against 59. Also A hosted endpoint, with nothing to install.

| Category | pen.dev | Subframe |
| --- | --- | --- |
| Reliability (16%) | 33 | 19 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 61 | 54 |
| Agent ergonomics (13%) | 66 | 47 |
| Security & auth (14%) | 33 | 44 |
| Payments & pricing (10%) | 38 | 33 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 59 | 65 |
| Transparency & trust (7%) | 53 | 57 |

| Fact (where they differ) | pen.dev | Subframe |
| --- | --- | --- |
| Vendor | High Agency, Inc. | Atomic Design Inc |
| Hosted endpoint | no (local only) | `https://mcp.subframe.com/mcp` |
| Transports | stdio | HTTP |
| Licence | Proprietary. The CLI package on npm carries a proprietary licence file, and the apps fall under the vendor's EULA | Proprietary service under Atomic Design's terms of service. `@subframe/cli` and `@subframe/core` are marked ISC in their package files and the Claude Code plugin MIT in its manifest, with no licence file in the repository |
| Tools exposed | 6 | 46 |
| Read-only variant documented | no | yes |
| llms.txt | no | yes |
| Terms last updated | 2026-10-06 | 2026-01-22 |
| Privacy policy last updated | 2026-10-06 | 2026-01-22 |
| Terms restrict automated access | yes | not found in the text |
| Terms restrict benchmarking | yes | not found in the text |
| Popularity | 3.5k npm/wk | 435 stars, 1k npm/wk |