Guy Podjarny - Spec Driven Dev From Single Player to Multiplayer to Ecosystem | DevCon Fall 2025 — Transcript
Full transcript
- 0:09Now, our next speaker is the uh is the
- 0:12uh founder and CEO of a little company
- 0:15called Tessle. Uh 18-month old company.
- 0:18Um GIO previously is he's a serial
- 0:21founder. He he he founded Blaze, which
- 0:23was acquired. He founded Sneak, a
- 0:25massively successful developer security
- 0:28uh company and organization that
- 0:29actually when we think about it, a lot
- 0:31of the challenges that that had in and
- 0:33around moving the the thought process,
- 0:36moving the moving the mindset of people
- 0:38to a developer security path is actually
- 0:41very similar to how we're thinking today
- 0:43about A&E development. And now we're
- 0:46going to talk about how AI can be done
- 0:48collaboratively. So please give it up
- 0:50for our first keynote speaker, Guy
- 0:51Pjani.
- 0:53>> [applause]
- 0:56[music]
- 1:03>> Hello everyone. Uh, welcome to the first
- 1:06inerson and native DevCon. Uh, love in
- 1:08person events, you know, like I think
- 1:10you you you convey things virtually. I
- 1:11consume things virtually, but nothing
- 1:13beats, you know, talking to people and
- 1:14engaging with them. And I hope you're
- 1:15all feeling that way. So, thanks for
- 1:17shipping in, especially in the rain here
- 1:19in New York. and uh uh and I hope you
- 1:21you enjoy the event and I look forward
- 1:23to meeting and learning from many of
- 1:24you. Uh I am Gapari or I am the
- 1:27founder and CEO of TESL. Uh and I'm here
- 1:30to talk about specdriven development's
- 1:32growth uh from kind of single player to
- 1:35really how do you use it in a team and
- 1:37how do you think about ecosystems? Um
- 1:39let me set the stage first. So hopefully
- 1:43we're all aligned that AI is
- 1:44transforming software development. It's
- 1:46not a little hiccup. It's not a little
- 1:47change. It's something that is
- 1:48substantial that is happening and we've
- 1:51seen a bunch of evolution already. We've
- 1:53had two kind of waves of what I think of
- 1:55as AI augmented software development uh
- 1:58with tools that were pioneered by
- 2:00copilot and cursor that autocomplete
- 2:02things better you know that that helped
- 2:04a lot that build in chat and allow you
- 2:06to talk to your code and understand
- 2:08things that cursor pioneered and then we
- 2:10uh in this last sort of especially 6
- 2:12months maybe 12 we've seen the rise of
- 2:14more true AI native which I think of
- 2:17them as more AI native dev tools because
- 2:19they're more about delegation they're
- 2:21more uh ask the agent to do a thing for
- 2:24you and then interact with it. So, it's
- 2:26a it's a much more substantial change
- 2:28for us and there's a lot to learn. And
- 2:31while all of these tools are are
- 2:32valuable in their own right, they've all
- 2:34kind of consolidated towards this
- 2:36agentic behavior. Uh and I think it's
- 2:38pretty clear that that is the future.
- 2:40So, I'll focus on where is that taking
- 2:43us? You know, how do we make this
- 2:44agentic development work?
- 2:47So, the reality today is that agents are
- 2:50are super powerful, uh, but they're
- 2:52massively unreliable, right? They're
- 2:53sort of sometimes spooky, sometimes
- 2:54kooky. You know, they're they're uh
- 2:56they're they're amazing and they do
- 2:58these things that astound you, but then
- 2:59they just make these foolish mistakes.
- 3:01Um, they're also very untrustworthy.
- 3:03They'll tell you something is done when
- 3:05it isn't really. They will break things
- 3:06along the way as they, you know, you ask
- 3:08them to build a feature, they'll burn
- 3:09down the house to to get it done. Uh,
- 3:11and so they're very powerful, uh, but
- 3:14they're kind of hard to use. Um, and
- 3:17this creates this capability reliability
- 3:19gap, you know, and you see studies like
- 3:21this one from meter where they they
- 3:25assess, you know, how how much do
- 3:27developers think AI tools will make them
- 3:30better. And you see this is the bar at
- 3:32the left and people developers, well, I
- 3:34think it's going to make me faster. I'll
- 3:35complete something faster. And then they
- 3:36observe how long it actually takes them
- 3:38to do it. And it turns out it actually
- 3:40was slower. There's a lot of caveats, a
- 3:42lot of flaws in this study and in any of
- 3:44the others. It's a very complex area,
- 3:46but I think everybody relates to the
- 3:48fact that it's not easy to turn this
- 3:51power into improved productivity into
- 3:54something that actually works.
- 3:57And and so what do we do about it? Well,
- 4:00what we can't do about it is say, you
- 4:02know, bury your head in the sand like
- 4:04let's not use agents is tempting. And,
- 4:06you know, a good number of people,
- 4:08probably none in this room are uh are
- 4:10saying that. Uh but you know it's
- 4:13clearly shortsighted. I mean this is a
- 4:15technology that's too powerful that uh
- 4:18to to kind of ignore or think it would
- 4:20fade away. It's here. It's going to
- 4:22shape our development. And we need to
- 4:24think about how do we embrace it? Not
- 4:26how do we ignore it? And so the real
- 4:28question is how do we help agents? How
- 4:30do we help agents succeed and close this
- 4:33capability reliability gap?
- 4:36Let's look a little bit at a at a
- 4:38history of attempting to do so. You
- 4:39know, this is uh our quest for silver
- 4:41bullets that would make LLMs work uh the
- 4:44way we want, right? And a bit of a loose
- 4:46timeline. We start off with, you know,
- 4:48this is us as the industry thinking
- 4:50about fine-tuning. Hey, we're going to
- 4:51tell the LLM, here are like tens,
- 4:53hundreds, maybe thousands of examples of
- 4:56how I like to code, how you code in my
- 4:58environment on it, and the LLM's weights
- 5:00will magically adapt uh and work like
- 5:03that. And it turns out that this works
- 5:05very well for brand new skills, for
- 5:07cases in which you're teaching the LLM
- 5:09to do something that it didn't know
- 5:10before. But if it already has opinions,
- 5:12if it already knows how to code, it's
- 5:14very hard to sway it. It's kind of like
- 5:15people, you know, we if if can't teach
- 5:17an old dog new tricks, right? It's hard
- 5:19to sway someone will behave. And so
- 5:22fine-tuning is useful, but it's not a
- 5:24silver bullet. And in fact, in many
- 5:25cases, uh it is it is hard to to really
- 5:28have it shine.
- 5:31The second kind of wave of technology of
- 5:33this will solve our problems was was
- 5:35rag. It's like I will take my prompt and
- 5:38I will put it into this magical kind of
- 5:40embedding algorithms and vector
- 5:41databases will pull out the right
- 5:43context that I need everything precisely
- 5:45that I need to know to be able to
- 5:47address this problem. And again rag very
- 5:49powerful when you have your own keywords
- 5:51and terminology and things like that but
- 5:54uh context gathering is more complicated
- 5:56than that. uh there's there's a lot of
- 5:58subtlety often time things that are not
- 5:59in your prompt they're not in that
- 6:01initial path and so it remained a useful
- 6:03tool but was deemed not uh not a silver
- 6:06bullet
- 6:08um the next kind of this will save us
- 6:10all was the world of big context you
- 6:11know what we don't need to worry about
- 6:12all this stuff you know we've got like
- 6:14million token 2 million token context
- 6:16windows we'll just tell it everything uh
- 6:19and it will figure it out it'll just
- 6:20sort of know what to do and it turns out
- 6:22you know like I often get uh the like
- 6:25through my career I've gotten the often
- 6:26times the guidance that says if you have
- 6:2810 smart things to say and you say all
- 6:30of them each of them will get less
- 6:32attention than if you said three of them
- 6:34uh and and I still struggle to not say
- 6:37everything I think but uh it but it's
- 6:39true you know if you say fewer things
- 6:41each of them gets more attention and
- 6:42NLMs are the same they if you if you
- 6:45give it more information in its context
- 6:46each of these bits would get less
- 6:48attention it would be less focused and
- 6:50we'll show a little bit of that in a sec
- 6:53and so we get into modern world uh and
- 6:55we have these two additional tools. One
- 6:57is agentic search. You know what? Let's
- 7:00delegate the actual problem of context
- 7:02creation to the agent. Let's give it
- 7:04tools to find the information. That's
- 7:06what we do as humans. We go, we Google,
- 7:08we look at files, we uh we do that work.
- 7:10And that is useful, but again, it's
- 7:12useful when it's constrained. If you
- 7:15tell someone just just go find, you
- 7:17know, the information about anything,
- 7:19it'll take time to find it. It'll take
- 7:22uh you might find the wrong information.
- 7:24uh and you know it's a in it's both
- 7:26inefficient and unbounded and you can
- 7:28get down rabbit holes that really kind
- 7:30of make things worse and so it's a very
- 7:32very powerful tool. We'll refer to it
- 7:34back again but again it didn't just
- 7:35solve the problem because there's
- 7:37another piece that we need on top of
- 7:38that and that is context engineering and
- 7:40that's the sort of the state of affairs
- 7:42today which is you actually have to give
- 7:46up on the magic solutions and think
- 7:48about what do you want to tell the
- 7:50agent? what information does the agent
- 7:52need to succeed? And I love uh this is
- 7:55uh Toby, the uh founder and CEO of
- 7:57Shopify. He's a very serial guy, super
- 8:00smart guy, and he was on the podcast uh
- 8:02uh a couple of months ago. And I like
- 8:04his quotes here, which is I like the
- 8:05term context engineering because I think
- 8:07the fundamental skill of using AI well
- 8:10is to be able to, and this is the key
- 8:11word, a state of problem with enough
- 8:14context in such a way that without any
- 8:16additional pieces of information, the
- 8:18task is plausibly solvable. I love that
- 8:20it's this notion of like let it lean
- 8:23into intelligence but don't assume mind
- 8:25readading you know like tell it what it
- 8:27needs to know so that it can succeed.
- 8:31So context engineering in my mind and I
- 8:34might be biased is basically the same as
- 8:36specs. You know this is about we just
- 8:38had this long conversation about you
- 8:39know should we call something spec or
- 8:41context. uh it doesn't really matter
- 8:42like for me it is about getting out of
- 8:45your head and out of your knowledge
- 8:46getting the the nuggets of knowledge
- 8:48that you need to uh give the agent to
- 8:50succeed and so I'm going to use the term
- 8:52context and specs interchangeably
- 8:54throughout this talk that's the way I
- 8:55see the world
- 8:58so I'm going to go into that sort of
- 8:59single multi-ecosystem player but before
- 9:02that I want to remind us that you can't
- 9:04optimize what you can't measure this is
- 9:06a known phrase in the world of software
- 9:08development but really mostly you hear
- 9:10it about ops because in ops we are
- 9:13familiar with these systems that
- 9:14sometimes behave well and sometimes
- 9:16don't right the the servers sometimes
- 9:17work sometimes don't sometimes they
- 9:19crash and so we have to measure them so
- 9:20we know what's happening so we can
- 9:21optimize it now we have the same
- 9:23statistical behavior in our development
- 9:26you know we have these statistical
- 9:27creatures agents they build stuff
- 9:29sometimes they work sometimes they don't
- 9:31and that means two things one we need to
- 9:33leave the notion of agents can
- 9:35absolutely do this or cannot absolutely
- 9:38and embrace a statistical number around
- 9:40their success uccess rate and two is we
- 9:42have to measure that we have to think
- 9:43about how do we evaluate how do we
- 9:44assess success and I'll try to give some
- 9:46data to back some of my statements in
- 9:47this talk
- 9:50so now we'll actually get to the thing
- 9:51that is on the title which is let's talk
- 9:53about uh single player how do you do
- 9:55context engineering in a single player
- 9:57context so um just to demonstrate a
- 10:01little bit the the base this is a a um a
- 10:04little sample to-do application with a
- 10:06Jurassic theme that I worked very hard
- 10:08on uh to just sort of demonstrate
- 10:10And the base context that an agent has
- 10:13is your project. Here I'm asking the
- 10:16agent to add an edit button to each of
- 10:18the to-do items in my list. And you'll
- 10:20see the agent automatically go off and
- 10:22read files in the project. It doesn't
- 10:24read all of them. It's already doing a
- 10:26gentic search to load uh some of that
- 10:29content. Uh and then it would load that
- 10:32code, understand that code, and uh
- 10:36sorry, I'll just sort of pause here. uh
- 10:38and um uh it it can load loads that code
- 10:41and reads that into context. So, I
- 10:43didn't need to tell it what the to-do
- 10:44item is. I didn't need to tell it where
- 10:46to put that button. It had enough
- 10:48information in the code and this is the
- 10:50base context that's important. However,
- 10:53you'll notice for instance that it
- 10:54created this blue edit button and that
- 10:56doesn't fit my beautiful Jurassic theme.
- 10:58Uh and it turns out that in the code
- 11:01some information is not there. It
- 11:02doesn't know that I want to stick to my
- 11:05theme colors. And so let's tell it to do
- 11:08that. So we can add explicit context
- 11:11that doesn't rely on agentic search like
- 11:14an agent MD file that says always stick
- 11:17to the theme colors used British
- 11:19spelling and it will go off and I will
- 11:22ask the same action you know I will say
- 11:23add an edit button and it will go off.
- 11:25it'll do the same type of like dynamic
- 11:27loading and uh maybe I'll sort of spare
- 11:30us a moment here uh as we get to the end
- 11:33you will see that it indeed created uh
- 11:35the button with my beautiful theme
- 11:37colors uh and and so this is this is 101
- 11:40of context engineering at at the base
- 11:42your project's context your project's
- 11:44code is the agent's context how well
- 11:47documented it is whether it is confusing
- 11:48and has references to old data
- 11:50structures that you have uh how um uh
- 11:53reasonable are your file names all of
- 11:55Those things help the agent load the
- 11:57right files, but then there's going to
- 11:59be some information that's not in the
- 12:00code and you put in your explicit agents
- 12:02MD, claude MD, cursor rules, local
- 12:05context. You probably know much of this
- 12:07already. The challenge is this is nice
- 12:10when you want to tell it stick to the
- 12:12theme colors, but typically you have a
- 12:14lot more to say. You there's just a lot
- 12:16that you want to tell it uh about how to
- 12:18work in your environment, in your style.
- 12:21And as we talked about before, if you
- 12:24tell it 10 things, it's going to get,
- 12:26you know, give each of them less
- 12:27attention than if you told it three. Uh,
- 12:29and so this is uh a problem. Before I
- 12:32talk about how to solve it, let's maybe
- 12:34back that claim that this is a problem
- 12:36with some data. So to do that, we took a
- 12:40little uh game, the team took a little
- 12:42sort of dodge the blocks game uh that
- 12:44that was vivecoded and asked uh the
- 12:47asked an agent in this case Claude code.
- 12:49Actually we tried three agents say add a
- 12:51login to this like add sessionbacked
- 12:53authentication so this game will be
- 12:55behind the login. The other thing we did
- 12:56is we created again with agents uh an
- 12:59evaluation scorecard like how good is
- 13:01the security of this thing that you've
- 13:04just added just like a benchmark that
- 13:06are standards today for good rubrics and
- 13:08then we ran that in three different
- 13:10modes. One is we ran the agents without
- 13:13any context and we scored them. The
- 13:15second is we put into the agents MD or
- 13:17the equivalent uh the OASP the open web
- 13:19application security project uh guidance
- 13:22around authentication about 3 kilobytes
- 13:24of data and the second is the longer 20
- 13:27kilobytes of full security guidance that
- 13:29includes the 3 kilobytes there's no word
- 13:31that didn't exist in the second one and
- 13:34indeed as we ran this we saw and I'm
- 13:37just sort of you know uh this is no
- 13:39surprise that without any guidance the
- 13:43agent scored a 65 85% score and with the
- 13:47guidance with the precise guidance it
- 13:48got 85% score and if we told it more
- 13:51things it got a lower score it got 81.
- 13:54So this was good and it's already
- 13:56validation. We need to know that even
- 13:57though we expect this behavior now we
- 13:59have a bit more confidence and there are
- 14:01many examples of this but also we find
- 14:03information that is maybe a bit
- 14:04unexpected. For instance we ran this on
- 14:08three different agents. We ran it on
- 14:10claude on codeex and on cursor and what
- 14:13you can see is they all fared about the
- 14:16same mediocre results without any
- 14:18guidance. There are many pitfalls that
- 14:19you can have from a security perspective
- 14:21when you add a login page, but there's a
- 14:24big difference in how they handle the
- 14:25deeper context. Claude shined when you
- 14:27gave it precise instructions, but
- 14:28dropped a fair bit uh when you gave it
- 14:30the longer instruction. Codeex didn't do
- 14:32as well in total, but dealt with the
- 14:34longer context a lot more. And it's
- 14:37interesting because it's not obvious to
- 14:39people that not all agents listen the
- 14:42same. You we told them the same words.
- 14:44Some of these actually use the same
- 14:45model behind them, but agents process
- 14:48and make many decisions. And you know,
- 14:51granted, there are 10 runs behind each
- 14:52of these columns. So maybe there's also
- 14:54not enough data for statistical
- 14:55significance, but the results are
- 14:57substantially different. And you have to
- 14:58think not just about what is the
- 14:59question you're asking and the
- 15:00saturation, but also who are you asking
- 15:02it of?
- 15:05So, so we have this challenge. We want
- 15:07to tell agents a lot of things and they
- 15:10uh you know, we can't because it's going
- 15:12to deteriorate their performance. what
- 15:13do we do? So, it's a broader problem and
- 15:16there are a lot there's a lot to say
- 15:17about it, but one common pattern is the
- 15:19separation between rules and knowledge.
- 15:22Rules would be a small amount of data
- 15:24that you're providing it that you're
- 15:25kind of shoving down their throat.
- 15:27You're saying this will be in your
- 15:28agent. going to see this every single
- 15:30time and they have to be succinct and
- 15:32what they should do is they should
- 15:34include links and references to guide
- 15:36agentic search around where can it fetch
- 15:38additional information and that is the
- 15:40knowledge and I'll give an example from
- 15:42Tesla's content. So hopefully many
- 15:45people on this uh uh in this event uh
- 15:48here or virtually know that Tesla has a
- 15:50spec registry and we it's a a dependency
- 15:54system for knowledge. you can publish
- 15:56context into it in this form we call
- 15:58tiles and then you can consume that down
- 16:00to your uh to your consumers right to
- 16:03your agents uh and it will adapt it to
- 16:06the local agent and you can do it for
- 16:07your context but we also pre-populated
- 16:10the registry with over 10,000 specs or
- 16:14context uh that uh that that helps
- 16:17agents use open source libraries better.
- 16:19We've analyzed those libraries, we've
- 16:21iterated, we've evaluated and we created
- 16:23those. So let's let's look a little bit
- 16:25at what is the structure of those. Um in
- 16:29first of all we define a knowledge base.
- 16:31So well what is the knowledge that you
- 16:33want? So you do that in this tessle.json
- 16:35file. In our example there are
- 16:36variations of it we'll touch uh to say
- 16:39this is the information I want. In this
- 16:40case I have a bunch of libraries. I want
- 16:42to know how to use them. And then you'll
- 16:44see that each one of those is fragmented
- 16:46into pieces. So the agent doesn't need
- 16:49to suck it all up right away. Especially
- 16:51for some of these libraries, there's a
- 16:52lot to say. You don't want to hog the
- 16:54context window. So there's a bunch of
- 16:56different files.
- 16:58The second thing we would do is we will
- 17:00put a little bit of knowledge or a
- 17:02little bit of rules in the agents MD
- 17:04file and we'll say here's a link to your
- 17:06knowledge. Uh we actually it's a bit
- 17:08longer over here but we also give a
- 17:10little bit of instruction of uh what is
- 17:12the structure of the knowledge you might
- 17:13find to the agent but it's a very small
- 17:16amount of context that is in the roles
- 17:17and always loaded. And then if you click
- 17:20that knowledgemd file, you will get a
- 17:22markdown file that the agent can easily
- 17:24find out which libraries do you have a
- 17:26little bit of information about them and
- 17:28where can it learn more and then down
- 17:30the rabbit hole it can learn more. It
- 17:32has an index file it explains about in
- 17:34this case next.js and then it can in
- 17:38that file find links to additional
- 17:39information. So this is like a human
- 17:41clicking links on a website
- 17:43[clears throat] right you have a summary
- 17:44thing you're expanding a section or
- 17:46you're clicking through and it's very
- 17:47effective. This is a good way to give
- 17:50the agent uh a way to find the right
- 17:53information. Lean into its agentic
- 17:55search capabilities, but don't ask it to
- 17:58sort of browse the web and just figure
- 17:59it out.
- 18:02So hopefully at this point you're
- 18:03saying, well, show me some data. I
- 18:06realized as I was building it that uh
- 18:07this is a Jaring Maguire reference and
- 18:09not everybody knows that. It might be
- 18:11like a my age is starting to defer of
- 18:13it. Like it does say show me the money
- 18:15typically. Um so okay can we see some
- 18:18data right I make this claim that this
- 18:20is a good way and a good effective way
- 18:21to to make the agents work. Let's see
- 18:23some data. I'll show two examples of
- 18:25this. First is uh thanks to the great
- 18:28work that uh the team at Versell has
- 18:31done on Nex.js. So Nex.js JS is a very
- 18:33well uh wellused very popular JavaScript
- 18:36framework that is maintained and built
- 18:39today by the Verscell team and they
- 18:41published as a thought leader in the AI
- 18:43space uh a benchmark about that tries to
- 18:46measure how well can agents use Nex.js
- 18:49and they created about 50 different test
- 18:51cases uh and uh they ran it through
- 18:54different agents to see how well they
- 18:56can address those. It's interesting, by
- 18:59the way, immediately to see that even
- 19:01though Nex.js is so popular and has so
- 19:04much content, it's like the sweetheart
- 19:05of the training data, right? It's well
- 19:07doumented. It's an amazingly like clear
- 19:10set of data. The top agents, the ones
- 19:13that did the best, still only got a 42%
- 19:15score in this benchmark. And so that's
- 19:17already interesting and a bit sobering.
- 19:19But it goes to show, okay, can we
- 19:21improve this with context engineering?
- 19:22and in general that if you measure this
- 19:25now I bet you all the agents are now
- 19:27working on optimizing it and so our
- 19:30question was okay we've done this can we
- 19:32optimize this with context can we test
- 19:35our uh uh our our knowledge like these
- 19:38tiles that we create do they actually
- 19:39make it better and we ran this eval
- 19:42because we already had the eval so we
- 19:43just had to compare the two test cases
- 19:45and we're happy to see that yes yes yes
- 19:47we can with the knowledge the success
- 19:50rate like for us it was about 40% % in
- 19:53our uh uh test environment. Success rate
- 19:55of using SJS on this benchmark, it
- 19:58jumped up to 92% if we got that info.
- 20:00This is if we got you know the very
- 20:02thoroughly created piece of information.
- 20:04But we also find for instance that a
- 20:06smaller prompt midway that just guides
- 20:08the agent to look at the things that you
- 20:10care about. Uh in this case, some
- 20:13linting and some build errors actually
- 20:15also bumped up the process
- 20:16substantially. So sometimes it's
- 20:17knowledge and sometimes it's steering
- 20:20around what is it to pay attention to.
- 20:24This is great for next.js
- 20:25[clears throat] but this was a very
- 20:26thorough benchmark set that required a
- 20:29lot of attention. We can't do that for
- 20:31everything. But what you can do when you
- 20:32evaluate your content or when you have
- 20:34something that is uh you don't have the
- 20:36sort of the bandwidth to create a deep
- 20:38benchmark for is that you can use LLMs
- 20:40to create evaluation data. And so we
- 20:43took 270 random libraries and we asked
- 20:46the LLM to create test exercises for
- 20:49them, a scorecard to evaluate how well
- 20:52they did on that test and then we ran it
- 20:54through agents. The data I have here is
- 20:56for cloud code. We saw similar data for
- 20:58cursor and then eventually you ask an
- 21:00LLM to judge the result with that
- 21:02rubric. And indeed when we ran that we
- 21:04saw that on average across those 270 we
- 21:08bumped up the success rate from about
- 21:1060% to about 81% uh in open source in
- 21:14agents ability to consume open source
- 21:15across these 270 libraries and we did
- 21:17that with a little bit of a shortening
- 21:19of the time. So the agents were a lot
- 21:21more successful in a little bit less
- 21:22time a little bit faster which was
- 21:24really encouraging. So this was great
- 21:26and this is again the validation part.
- 21:28We also had you always find these bits
- 21:30of information that you don't know how
- 21:31to expect. uh some interesting
- 21:33information about the age of a library.
- 21:35And so this graph shows with the same
- 21:37test the success rate of the agent. This
- 21:40is cloud code across uh correlated to
- 21:44the uh age of the libraries. The
- 21:46libraries at the left are the oldest.
- 21:47The libraries on the right are the
- 21:49newest that this is release date just as
- 21:51a simple measure. And it's interesting
- 21:53to see how the libraries that are 5 to
- 21:5510 years old, those are the ones that
- 21:57the agents do the best with. And we've
- 21:59seen this with other agents as well. Uh,
- 22:01and the distance is substantial. And
- 22:03that makes sense because very old
- 22:05libraries, they might have they might
- 22:07have confusing information on the web.
- 22:10Uh, maybe they don't have as much web
- 22:11representation if they're truly old. And
- 22:13the very new libraries often times they
- 22:15haven't accumulated enough information
- 22:16on the web and some of their data is
- 22:18actually after the training data. And
- 22:20our theory was that with uh with the
- 22:22tiles, we actually can flatten that
- 22:24line, right? We because we gave them the
- 22:26information, they have it, so they
- 22:27should use it. And indeed, we've seen
- 22:28that we elevate the result more broadly.
- 22:31And this was useful because it matches
- 22:32our kind of anecdotal experience that um
- 22:36using this type of knowledge, using the
- 22:37right context, sometimes just helps and
- 22:39sometimes it turns it from it doesn't
- 22:41work to it works.
- 22:45Um I'll move on to multiplayer, but just
- 22:48one thing to say is that in context
- 22:49engineering is actually a lot more than
- 22:50what I'm showing right now. And there
- 22:52are many many different tools and one
- 22:54notable one is the ability to use a sub
- 22:56agent in claude and now a few other
- 22:58agents to be able to give it its context
- 23:01and focus it. So there's a lot more to
- 23:02do here and it's a worthy domain to
- 23:04invest in.
- 23:07So with that let's talk from single
- 23:09player talk about multiplayer. In
- 23:10multiplayer, the question is in your
- 23:13team, in your organization, what context
- 23:16do you want to provide and when? What
- 23:19are the ways in which you can share
- 23:20context across the team? I'll talk about
- 23:23three versions of this. The first and
- 23:26kind of easiest most sort of uh direct
- 23:29way to share context is to put stuff in
- 23:31the repo. As we said, the project itself
- 23:34is the base context for an agent. And so
- 23:37if you check in an agent MD file,
- 23:39anybody that uses that repository would
- 23:40load it. It's the repo or the path
- 23:42within the repo. This is great and you
- 23:44should do it and it is a perfect fit for
- 23:47things that are repo specific knowledge.
- 23:49Right? This is documentation about how
- 23:50this application behaves or things like
- 23:52that. Awesome. Perfect place to do it.
- 23:54Highly recommended. Uh where it slightly
- 23:57falters is uh one is cross repository
- 24:00information. your be best practices,
- 24:02shared libraries and all those feels a
- 24:04bit odd to check those into a
- 24:06repository. Would you check them into
- 24:08multiple repositories? You might want a
- 24:09different solution. And the second is uh
- 24:12and I'm picking a little bit on backlog
- 24:13MD over here. You know, it's a great
- 24:15framework. We had a great workshop
- 24:16yesterday about it. Um and you can see
- 24:18though that you know those who adopt
- 24:20agents and lean into them, what you find
- 24:22in the repos is you find many duplicate
- 24:23files. You find your sort of Gemini MD
- 24:25and cloud MD and agent MD and cursor
- 24:27rules and you'll find skills. You'll
- 24:28find GitHub stuff.
- 24:30and and that's not awesome. Uh and it's
- 24:33not that you have this many files that
- 24:34is the problem, but rather that they are
- 24:36duplicative. There's often content that
- 24:38is very similar within each one of them.
- 24:40So that's a challenge.
- 24:43The second tool that you have to
- 24:45accumulate and to provide shared context
- 24:48amongst your team is to give agents
- 24:50tools to gather context. uh most common
- 24:53is of course browsing the web but also
- 24:55things that are more focused like hey
- 24:57use this to uh uh this MCP tool to be
- 25:00able to go and fetch uh code from GitHub
- 25:03repositories and load them. So this is
- 25:05I'd say you know first of all super
- 25:07useful for discovery and exploration
- 25:09like you know you you don't know which
- 25:10library you're going to use clearly you
- 25:12don't have the context for that library
- 25:13as you're exploring you should have
- 25:15dynamic tools to go and fetch that. It's
- 25:16also great for dynamic data like uh uh
- 25:19production data about how your system
- 25:21ran or you know something that is
- 25:22constantly changing. So for those it is
- 25:24amazing. Uh it is not great when there's
- 25:28a high potential to get the wrong
- 25:29answer. Versioning is a is a strong
- 25:32example of that. If you're using a
- 25:33version that's not the latest and your
- 25:35agent went to the latest GitHub repo,
- 25:37it's going to get the wrong information
- 25:38to operate with. And for complex topics
- 25:42where there's subtleties, you know,
- 25:43authentication related topics or um just
- 25:46sort of complex environments,
- 25:49it's also highly inefficient for
- 25:52repeatedly needed info. So let's say you
- 25:55can go off and find the relevant commit
- 25:57at the relevant repo and read the code.
- 25:59If you need this information seven times
- 26:01a day, you know, five days a week, why
- 26:05like why wouldn't you sort of gather
- 26:06that context one time, store it,
- 26:08evaluate it and then optimize for that?
- 26:11Which gets me to the third mode which is
- 26:13today kind of the cutting edge and it's
- 26:16the notion of curated context or curated
- 26:18knowledge. What you would have seen is
- 26:20over the last couple of months you've
- 26:22seen a lot of progress from all the big
- 26:24agents uh uh providing reusable context
- 26:28frameworks. So they have you have you
- 26:30saw claude skills you saw cursor team
- 26:32rules you saw GitHub copilot spaces uh
- 26:35and you know these are these are kind of
- 26:37acknowledgements from these agent
- 26:39companies to say well we don't want the
- 26:40agent to reinvent it every time we
- 26:42actually want to allow you to share
- 26:44things and to share practices and that's
- 26:46great I highly recommend these platforms
- 26:48you should learn about your environment
- 26:49for it they're great for cross
- 26:51repository knowledge uh they're great
- 26:53when you're using often times you start
- 26:54seeing people use uh maybe like a you
- 26:57have a security code review bot that
- 26:59runs in your review surrounding, but
- 27:01that same context, you also want it when
- 27:03you're building locally and maybe when
- 27:04you're assessing an incident with
- 27:06another agent. So, it's great to have
- 27:08not just crossdevelopment repo, but also
- 27:10cross use case knowledge. Uh, and
- 27:12because they're built natively, they
- 27:14tend to be kind of nice and elegant in
- 27:15terms of how they interact, you know,
- 27:16clawed with its skills, cursor with its
- 27:18rules, etc. Uh, they're a bit of an
- 27:20overkill for single repo information.
- 27:22Maybe that's not too bad. But really the
- 27:24biggest challenge with them is that they
- 27:26are single agent. Um and that kind of
- 27:29begs the question of do we think long
- 27:31term that knowledge and context should
- 27:34be managed per agent, right? Do you
- 27:36think in your organization, in your
- 27:38practice, do you expect that you would
- 27:39use one agent for your org over time?
- 27:43And I think the answer to that is no.
- 27:45Like I think just like any technologies,
- 27:47technologies will be better at one thing
- 27:49versus the other. They will move. they
- 27:51will change. Companies are big. People
- 27:53will have preferences
- 27:55and that knowledge as a whole should be
- 27:57something that is a core competency of
- 27:59the knowledge that you have and it
- 28:01should be adapted per agent but it
- 28:02should be your asset that is broader. So
- 28:05that's the approach we have at Tessle.
- 28:06You've sort of seen a bit of this
- 28:07already. We have the Tessle JSON and
- 28:09when you install this knowledge then it
- 28:12will it will adapt it to the relevant
- 28:15agent. It will store it as a cursor role
- 28:16or it would store it as a as an agent MD
- 28:18or whatever that is. Uh and then also
- 28:20once we download that knowledge, the
- 28:22knowledge is there as files and so you
- 28:24can use it in whatever way that you
- 28:26want. We do provide tools to make it
- 28:29easier and better to work with it. We
- 28:30want it to be seamless, but you're not
- 28:32locked in to you need to use those tools
- 28:34if you want to use different tools to
- 28:36consume it. So we think this is
- 28:37important when we think about uh uh kind
- 28:40of broader long-term context management
- 28:42and development.
- 28:44And in fact, we're doubling down on
- 28:46this. And just as a slight plug here,
- 28:49you know, we are expanding the registry
- 28:51into a full-blown TESL uh agent
- 28:54enablement platform uh that will help
- 28:56you gather and and this type of
- 28:58knowledge like the packages you've seen,
- 29:00create and run evaluations for them,
- 29:02distribute them so that every repository
- 29:04gets its knowledge uh and then help you
- 29:06optimize that over time. Uh so this is a
- 29:08commercial product and if you're
- 29:10interested in being uh being part of it,
- 29:12uh come come talk to us, see us or email
- 29:15us at contact.io. fail if you're online.
- 29:19So that's a good segue for just the
- 29:21closing points around ecosystem context.
- 29:24And you know when I just sort of sang
- 29:27the sort of the uh the praises of why
- 29:29ecosystemwide context from the registry
- 29:32is helpful and you should use it and
- 29:33it'll help you today. But in the long
- 29:35run you do have to wonder who should
- 29:38create this type of open source context.
- 29:40know we we come along to someone else's
- 29:42library and we create these agent docs
- 29:44for them and we track them and that you
- 29:46know we do it today because it's helpful
- 29:48today and we want to help but long-term
- 29:50is that right
- 29:52and I think the answer is no like I
- 29:54think over time kind of open source
- 29:56context is really an aspect of agent
- 29:59experience and it is the creator's
- 30:01responsibility if you are an open source
- 30:03maintainer if you are a vendor it's your
- 30:06responsibility to have a great developer
- 30:07experience it's also your experience
- 30:10your responsibility to have a great
- 30:12agent experience. You know, it is it is
- 30:14in your control. It is something that
- 30:15you can choose where to invest and
- 30:18context is your best tool for that.
- 30:20Context is both your documentation and
- 30:21your UX. You know, you need to think
- 30:23about what is it that you say there. How
- 30:25do you distribute that to your users?
- 30:28You know, do you want this indeed to be
- 30:29single agent or multi- aent? And eval
- 30:32are your tests. They're your moment of
- 30:34defining what is correct and what is not
- 30:36correct. And so, you should invest in
- 30:38those. You should define them. And you
- 30:39should ask your users for feedback on
- 30:41when they work and when they don't work.
- 30:44And you're it's your responsibility, but
- 30:46you're not alone. You know, you have us
- 30:48to help with our technology with our
- 30:49platform on it. You know, feel free to
- 30:51talk to us. You have the amazing AI
- 30:53native dev uh community that you should
- 30:55tap and they will help you. And
- 30:57together, I think we want to create this
- 30:59successful methodologies and actual
- 31:02context that will help us all consume
- 31:04software together better. Uh and if we
- 31:06achieve all of that then we'll help
- 31:08we'll successfully put everything in the
- 31:10right context. Thank you.
- 31:16[music]
- 31:34>> [music]
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