Hacker News: pmkelly4444

We gave an AI agent eyes. It didn't even use them

pmkelly4444 — Mon, 01 Jun 2026 16:29:47 +0000

Article URL: https://www.agentvoyagerproject.com/captains-log/2

Comments URL: https://news.ycombinator.com/item?id=48359075

Points: 2

# Comments: 0

Skills vs. MCP vs. prompts: which agent setup works best?

pmkelly4444 — Tue, 26 May 2026 14:29:08 +0000

Article URL: https://www.agentvoyagerproject.com/captains-log/1

Comments URL: https://news.ycombinator.com/item?id=48280335

Points: 3

# Comments: 1

The Slop KPI Era: How Tokenmaxxing Is Making AI Worse

pmkelly4444 — Wed, 15 Apr 2026 16:58:58 +0000

Article URL: https://portofcontext.com/blog/welcome-to-the-slop-kpi-era-how-tokenmaxxing-is-making-ai-worse

Comments URL: https://news.ycombinator.com/item?id=47781886

Points: 4

# Comments: 0

Show HN: Python Local Sandbox Code Execution (Podman and Uv)

pmkelly4444 — Mon, 22 Dec 2025 13:02:44 +0000

The core idea: @sandbox(dependencies=["pandas"]) turns any function into one that runs inside an isolated Podman container with dependency caching built in on uv. You call it like a normal function, but the code executes with no access to your host filesystem, credentials, or processes.

from pctx_sandbox import sandbox

@sandbox(dependencies=["requests"]) def fetch_url(url: str) -> str: import requests return requests.get(url).text

result = fetch_url("https://example.com") # runs in container

Technical details:

- Uses rootless Podman for container isolation (all the Linux namespace stuff: PID, mount, network, user) - Maintains a warm pool of workers per dependency set, so there's no cold-start penalty after the first call - Dependencies are cached and installed once per unique combination - Resource limits enforced via cgroups

The security model is "defense in depth" – it's container isolation, not a VM, so it's not a perfect security boundary. But it's good enough that I'm comfortable letting Claude use it on my machine.

Would love feedback. Thanks!

Comments URL: https://news.ycombinator.com/item?id=46353821

Points: 4

# Comments: 0

Pctx-Py – Code Mode for Python Tools and MCP

pmkelly4444 — Tue, 16 Dec 2025 18:48:41 +0000

Article URL: https://portofcontext.com/blog/pctx-python-is-here

Comments URL: https://news.ycombinator.com/item?id=46292602

Points: 2

# Comments: 0

New comment by pmkelly4444 in "A Python SDK That Saves AI Tokens with Code Mode"

pmkelly4444 — Tue, 09 Dec 2025 16:07:34 +0000

If you are building AI Agents in Python and want to improve token efficiency, please have a look at the RC of the pctx Python SDK

A Python SDK That Saves AI Tokens with Code Mode

pmkelly4444 — Tue, 09 Dec 2025 16:07:34 +0000

Article URL: https://pypi.org/project/pctx-client/

Comments URL: https://news.ycombinator.com/item?id=46206540

Points: 1

# Comments: 1

New comment by pmkelly4444 in "Open Source and Local Code Mode MCP in Deno Sandboxes"

pmkelly4444 — Fri, 21 Nov 2025 16:41:03 +0000

e2b.dev is focused on this space

New comment by pmkelly4444 in "Open Source and Local Code Mode MCP in Deno Sandboxes"

pmkelly4444 — Fri, 21 Nov 2025 16:34:42 +0000

yes! coming soon

New comment by pmkelly4444 in "Open Source and Local Code Mode MCP in Deno Sandboxes"

pmkelly4444 — Fri, 21 Nov 2025 16:34:21 +0000

this makes sense, we should support a model where the code snippets can all be stored on the filesystem rather than in the context window from the MCP response

New comment by pmkelly4444 in "Open Source and Local Code Mode MCP in Deno Sandboxes"

pmkelly4444 — Fri, 21 Nov 2025 16:20:40 +0000

got it, yes so currently this is built just for one user - one set of credentials, but passing user credentials through is something we want to add.

thinking a native connection to cloud auth managers is the best way to do this (clerk, auth0, etc.)

New comment by pmkelly4444 in "Open Source and Local Code Mode MCP in Deno Sandboxes"

pmkelly4444 — Fri, 21 Nov 2025 15:42:44 +0000

thank you, will get a more detailed benchmark out soon!

New comment by pmkelly4444 in "Open Source and Local Code Mode MCP in Deno Sandboxes"

pmkelly4444 — Fri, 21 Nov 2025 14:27:35 +0000

no dependency injection at the moment... this is something we are exploring. adding dependencies would require rebuilding the execution runtime, which is something we want to open up in the framework soon

New comment by pmkelly4444 in "Open Source and Local Code Mode MCP in Deno Sandboxes"

pmkelly4444 — Fri, 21 Nov 2025 14:26:19 +0000

hey! the way it works is that the llm is first given snippets in typescript that tell it how to use the various MCP tools. it then can code, in typescript, and execute all of the tool calls in the deno sandbox. so yes, it can only execute javascript, but this isn't meant to be a full arbitrary code execution env like E2B.dev is, this sandbox is only meant to be a place for MCP calls to happen.

we chose typescript because it's the most token efficient way to pass types and signatures to an LLM, with Python and Pydantic there are extra characters passed around

New comment by pmkelly4444 in "Open Source and Local Code Mode MCP in Deno Sandboxes"

pmkelly4444 — Fri, 21 Nov 2025 14:08:52 +0000

thank you!

on your second point, check out how we lock down the sandbox with a custom deno runtime! https://github.com/portofcontext/pctx/tree/main/crates/pctx_...

on third, will def get some benchmarks out... we setup OTEL so we have the data

New comment by pmkelly4444 in "Open Source and Local Code Mode MCP in Deno Sandboxes"

pmkelly4444 — Fri, 21 Nov 2025 14:02:16 +0000

nice! will follow your progress! love that this runs locally as well

Show HN: Pctx – OSS to build efficient AI agents with Code Mode

pmkelly4444 — Wed, 19 Nov 2025 17:31:07 +0000

Hey HN! I built pctx, a framework that lets AI agents execute code directly instead of making tool calls to save on tokens on MCP.

I've been working on code generation in Rust for 2 years, mostly fighting with OpenAPI specs that are either missing or incorrect. MCP's self-documenting nature made this a fun project to tackle since the servers describe their own capabilities accurately. I could focus on building execution sandboxes instead of wrestling with bad specs. After seeing how Cloudflare and Anthropic's Code Mode implementations reduced tokens, I decided to build an open-source version with a focus on correctness and local-first design.

pctx prioritizes reliability (TypeScript validation pre execution) and DevEx (no dependencies, 100% local, built-in MCP auth)

Technical details: - Two locked-down Deno sandboxes: - TypeScript compilation/validation (pre-execution) - Execution with MCP network access only - Compiles to a single binary, no dependencies - Built-in TypeScript code generator and MCP auth utilities - Uses the official rmcp client/server within the execution runtime

Coming soon: - Automatic authentication of the pctx server - Python and TypeScript SDKs for using natively in agent frameworks - Anything else people want - One-click cloud deployment (see website)

GitHub: https://github.com/portofcontext/pctx Website: https://portofcontext.com

Would love your feedback on this. Thanks!

Comments URL: https://news.ycombinator.com/item?id=45982258

Points: 1

# Comments: 0