# Pen.dev — WebMCP observations

Canonical: https://mudpie.ai/directory/webmcp/accelerators-2026-09-20/speedrun-70f8efdb-0078-4960-9e74-9cf4393d610b/

- Roster: a16z Speedrun / SR005
- Roster observed: 2026-09-20
- Official profile: <https://speedrun.a16z.com/companies/pendev>
- Listed website: <https://pencil.dev>
- Browser: 153.0.8010.50

## Default Chrome

Not observed in this window. Final URL: <https://www.pen.dev/>

Window: 2026-09-20T21:26:01.842Z to 2026-09-20T21:26:04.064Z.

Tools: Not observed in this window.

Source SHA-256: a13198d96033ac580e0e444a91af4feb50d5994cff286daefe4d5876683e7d8f

## Experimental features enabled

Registration observed. Final URL: <https://www.pen.dev/>

Window: 2026-09-20T21:49:35.562Z to 2026-09-20T21:49:37.924Z.

Tools: open\_editor.

Source SHA-256: 828c62e7b48a055244f7c214098b06db67b59b43b0c7bb379377a4f3f12e2e15

## Limits

No tool was invoked. Registration does not establish execution, product quality, task success or adoption. Absence in one window is not website-wide absence.

[Study and methods](https://mudpie.ai/agent-readiness/measure-agent-distribution-without-counting-registrations/) · [Full dataset](https://mudpie.ai/research/native-webmcp-census-2026-09-20.json) · [Census directory](https://mudpie.ai/directory/webmcp/accelerators-2026-09-20/)