becoming an expert harness eng and sharing learnings pi-gui.com, openbench.run, computer-use-mcp @codexreleases @pichangelog

New York, NY
I will now work towards my goal of being an expert in harness engineering. Harness Eng Learning #1: Codex new compaction Previously codex asked the server to compact the convo at compaction endpoint, that returned an encrypted summary into the future model requests. New compaction instead saves working notes between context windows, starts with fresh context, and retrieve these notes through tool calls when needed. New compaction flow: 1. save state with notes.write_file tool call 2. reset context new_context 3. request for thread_hint to find notes to recover from 4. read from previous notes files, or history tool calls to recover context (notes.read_file, history.read_item) 5. retrieved content enters context as tool results and continue on with new messages Would be interesting to see an eval across long horizon tasks and compactions between the two compaction modes @pvncher . Also, this compaction mode is specifically only for Astra not Sol or others.
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the most obvious advantage Dots has over Instinct/Bot/Muse is computer use. Dots works pretty well spinning up tasks that work on your local laptop for computer use, sometimes it is just faster/more convenient to use the local laptop. Props to @AriX @conradev @JamesZmSun and team, computer/browser use has been and still is the most standout feature of Codex.
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Also forgot to add, the model is smarter/more capable
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Grok bot is a great product, but tbh I want to see non SpaceX ppl’s review on it. Whenever I see someone praising bot on my TL, I click into the profile and they’re at SpaceX, feels biased and more shilly. Maybe just me
was mostly using Instinct over Muse for personal errands, but just started giving @bot another go, and it's much faster than before. Instinct is still great for daily use and just using imessage, but I do anticipate connectors becoming more and more important, for example finances. Find myself drifting to bot today, especially if the new primary bot works well. Plus I think Cursor has the best product builders in taste and ux out of the AI companies. Is there some fix for notifications though @poteto @ericzakariasson? Feel like it over notifies me. Ex. it's notifying me every message on my phone, even if i'm on the app on my laptop.
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was mostly using Instinct over Muse for personal errands, but just started giving @bot another go, and it's much faster than before. Instinct is still great for daily use and just using imessage, but I do anticipate connectors becoming more and more important, for example finances. Find myself drifting to bot today, especially if the new primary bot works well. Plus I think Cursor has the best product builders in taste and ux out of the AI companies. Is there some fix for notifications though @poteto @ericzakariasson? Feel like it over notifies me. Ex. it's notifying me every message on my phone, even if i'm on the app on my laptop.
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Anthropic should’ve stuck with plugins not mods, but great walkthrough by Lydia
A few of you asked what mods are, here's a quick walkthrough! They’re really just plugins with a few special functions that let your code run inside Claude Code, like middleware. (don't worry, you can just ask Claude to write them for you 😛)
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Matthew Lam retweeted
One promt, all of my degenerate past pi sessions and a couple of hours later
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Matthew Lam retweeted
1/ We're reimagining what it means for your agents to work with all your computers. Today we're excited to share Cua Spaces, built on Cua Driver and our virtualization stack, rolling out on macOS today. Download it now, it's free and source-available: spaces.cua.ai
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feel like Instinct is suddenly more proactive today. Wonder if they added more of the heartbeat use to proactively check for things to help with
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so is there a safe way to use my claude sub in @pidotdev without getting banned?
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Matthew Lam retweeted
got this in pi-gui but even cooler soon. Here's a sneak peek. @pidotdev extensions will be able to create custom desktop views, so you can have your own fully customized Pi-GUI experience! You'll also be able to add custom cards that show up across the app, in the transcript, composer window, side bar, and others. Here's a demo extension, where you can trace the agent's last turn, tool calls, latency, and usage. Fully updated with Pi v1.0 @badlogicgames :)
You can now mod Claude Code: - Change how it behaves - Customize the UI - Swap in your own features Write one with a few lines of TypeScript, or have Claude build it for you. Mods ship inside plugins, so you install them with /plugin in the CLI or desktop app. A few examples:
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aight gonna give @bot another try with Primary bot. Meta/Instinct have mostly felt the same for me. Not sure if i need separate bots yet, but hopefully they're faster and more differentiated now
Replying to @bot
We're also sharing our engineering team's Bots as templates you can install. Each one comes with skills, routines, and connectors to get you started. x.ai/bot/marketplace/enginee…
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Matthew Lam retweeted
Harness Learning #6: how @pidotdev handles prompt caching Prompt caching is one of the most important points in cost efficiency in using LLMs, and harnesses have the responsibility of sending requests that match a provider's cache policies. This is especially hard for harnesses like Pi that integrate with many providers, and they've just released a cool new cache warming feature! Pi has a cacheRetention setting that can be set to none/short/long, and gets translated through the provider adapter for each provider: ? Anthropic: cache-control markers get used in the request, and "long"=1h TTL ? OpenAI: caching is implicit, pi attaches the prompt_cache_key in request as the session id so that requests get routed to the right machine holding the cache. ? Bedrock also is cache markers ? OpenRouter, Fireworks, Baseten also get included a session id header for sticky routing For one off calls where the cache entry won't be used, Pi uses "none". For example in compaction summaries, since that exact summarization request won't be sent again, so writing it to the cache would be wasted.
Hello people of Pi. 0.86.0 is out now. It's a big one. - mid-conversation system messages - dynamic tools on supported models without losing the kv cache - cache warming on anthropic - faster -r/-c to resume - lots of fixes - /bug to report issues pi.dev/news/releases/0.86.0
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Did not know Google was coming in hot like that
Announcing Gemini 4 Argon, our new frontier model. Argon is built to sustain deep reasoning across complex, long-horizon workflows and delivers frontier performance in complex workflows across real-world software engineering, enterprise knowledge work like legal and finance, and cybersecurity defense. We’re also expanding the model’s output token limit to an industry-leading 1M tokens. Argon is currently rolling out to a set of trusted cyber defenders in the Fairwind Program, with broader availability as soon as possible.
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.@OmidMogasemi @pranathiperii can we get some navigation between threads of a project? Sometimes I need to be more hands on in the project threads, and right now I need to click "Threads" then find the thread to switch back between two of them. Maybe ctrl+tab switching, or some can end up on sidebar or something
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i also find these states often wrong, adding to it being harder to navigate and find threads
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was testing Fable 5.1 High on a more complicated task, but felt like it was harder to work with and understand than Opus 5.5. Going to just try out Opus 5.5 for everything, not sure I need Fable at this point. 5.5 med has been working wonders
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Matthew Lam retweeted
Now the RAM prices make sense.
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Love how Holly decided to handle this response. Also great job by both her and @romainhuet handling the live demo errors.
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I enjoy these little design touches
Thank you for all the @bot love on X - if you like this post you’ll notice a fun surprise!
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