WEBVTT 00:00.160 --> 00:01.600 So much as we started week two. 00:01.640 --> 00:08.480 We're now going to go through the core concepts of crew I, the sort of building blocks to understand 00:08.480 --> 00:11.320 how it works, and there's some similarities. 00:11.440 --> 00:13.560 First of all, there is an agent. 00:13.720 --> 00:21.800 An agent is basically the smallest the unit of work, an autonomous unit, which is related to an LM. 00:21.800 --> 00:27.520 It has an LM underneath it, and it has something called a role, a description of what it does, a 00:27.600 --> 00:30.040 goal and a backstory. 00:30.240 --> 00:33.040 And it can also have memory and it can have tools. 00:33.320 --> 00:36.520 And that is how an agent is defined. 00:36.520 --> 00:41.160 And you can remember back to OpenAI agents SDK definition. 00:41.880 --> 00:43.080 There is something new here. 00:43.080 --> 00:44.840 A task is another thing. 00:44.880 --> 00:48.000 And there wasn't an analog in the last framework. 00:48.160 --> 00:52.600 A task is a specific assignment that is going to be carried out. 00:52.600 --> 00:57.320 It has a description, it has an expected output, and it has an agent. 00:57.320 --> 01:00.240 So a task is assigned to an agent. 01:00.640 --> 01:02.880 So that is the distinction agents. 01:02.880 --> 01:04.400 And then tasks. 01:04.560 --> 01:14.170 And there can be multiple tasks for an agent, and then a crew is a team of agents and tasks, and that 01:14.170 --> 01:15.130 is simply so. 01:15.130 --> 01:21.810 A crew is the aggregate of the of the other two, and a crew can be can be has two different process 01:21.810 --> 01:22.650 modes. 01:22.650 --> 01:28.050 One of them is called sequential, and that is where it will simply execute each task in turn as it's 01:28.050 --> 01:28.690 laid out. 01:28.890 --> 01:31.250 And the other is called hierarchical. 01:31.250 --> 01:38.370 And that is where an LM will be used a manager LM in order to assign tasks to agents. 01:38.650 --> 01:42.410 So those are the two different modes that you can operate in. 01:43.010 --> 01:47.410 So that gives you these are the three core concepts to keep in mind. 01:47.970 --> 01:49.130 So how do we think about this. 01:49.130 --> 01:52.250 So so it's it's this these are lightweight concepts. 01:52.290 --> 01:58.730 And they're certainly reminiscent of last week I would say that it is a bit more opinionated than the 01:58.730 --> 02:00.210 OpenAI agents SDK. 02:00.250 --> 02:02.290 There's a bit more terminology. 02:02.290 --> 02:03.810 It's a bit more prescriptive. 02:03.810 --> 02:09.610 So as a clear example, if you look at the agent there, if you remember last week, agents just had 02:09.610 --> 02:10.570 instruction. 02:10.610 --> 02:12.850 An instruction was basically the system prompt. 02:12.850 --> 02:14.890 And you provided the instruction. 02:14.890 --> 02:17.570 And that's very unopinionated. 02:17.610 --> 02:21.410 You can choose to think about instructions however you want. 02:21.610 --> 02:26.810 Now with crew, an agent has a role, a goal, and a back story. 02:27.170 --> 02:29.130 So it's a bit more you can see immediately. 02:29.130 --> 02:36.450 It's more prescriptive in terms of how one is supposed to to prime the this, this, this LM, and how 02:36.450 --> 02:41.890 that is constituted into a system prompt is something that's, that's not immediately available. 02:41.890 --> 02:46.810 There are, in fact, ways that you can choose to set that you can sort of put in templates, but that's 02:46.810 --> 02:51.930 somewhat hidden from you at the, at the certainly at the beginner level, if you just use it out of 02:51.970 --> 02:54.930 the box, you have to provide the role, the goal, the backstory. 02:55.050 --> 03:00.250 And I think this is a really good example of the trade offs between these different frameworks, because 03:00.290 --> 03:05.770 obviously forcing us to think in terms of a role and a goal and a backstory is good, because these 03:05.770 --> 03:11.930 are all sort of good prompting practices to think about the context, to give the backstory this this 03:11.930 --> 03:14.890 is a a good, best practice at the same time. 03:14.930 --> 03:16.050 So so that's the benefit. 03:16.050 --> 03:20.340 The trade off is that we might not we might have a specific situation where we don't want to give a 03:20.340 --> 03:21.740 backstory that's not relevant. 03:21.740 --> 03:23.460 We want to think about it differently. 03:23.460 --> 03:26.260 And that is completely possible with AI. 03:26.300 --> 03:27.340 But it's going to be harder. 03:27.340 --> 03:30.260 We're going to have to then dig in and find out what's going on. 03:30.500 --> 03:34.700 And also if we're trying to debug a problem and we're not sure what's what's happening, we don't we 03:34.740 --> 03:37.300 don't have the same control over the system prompt. 03:37.340 --> 03:41.740 We just know that it's being constituted based on these various building blocks. 03:41.940 --> 03:47.340 So hopefully I give you this color because I want you to have a good sense of what are the trade offs 03:47.340 --> 03:49.220 in adopting these different platforms. 03:49.260 --> 03:51.060 And and that's a pretty important one. 03:51.780 --> 03:58.580 So a nice feature of crew is that you can do a lot of the definition of things like agents and tasks 03:58.620 --> 04:04.500 using configuration, which allows you to sort of nicely separate some of the text rather than having 04:04.500 --> 04:06.220 it embedded all over your code. 04:06.580 --> 04:12.580 So when you think about agents and tasks, those those, the two things that make up a crew, agents 04:12.580 --> 04:14.500 and tasks can be created by code. 04:14.500 --> 04:18.940 You can say agent equals my agent, my agent equals agent. 04:18.940 --> 04:24.900 Open brackets and then pass in a lot of things like the LLM to use and the role and the backstory and 04:24.990 --> 04:25.510 so on. 04:26.110 --> 04:31.590 Or instead of that, you can write a YAML file that looks a bit like this. 04:31.830 --> 04:35.030 We'll look at many of them in the course of this week, but it's a YAML file. 04:35.030 --> 04:41.550 If you're not familiar with YAML, it's a very simple, easy for humans to read kind of markup file. 04:41.670 --> 04:43.310 And and it looks a bit like this. 04:43.350 --> 04:50.910 And this is going to allow us to lay out a, a role, a goal, a backstory, and an LLM associated with 04:50.910 --> 04:53.830 an agent called researcher in this example. 04:54.070 --> 04:59.470 And that will allow us to separate out the configuration from the code. 04:59.750 --> 05:03.870 And whilst that is in some ways, as always there's some pros and cons. 05:03.910 --> 05:06.910 The the con is that it's a bit of something to get used to. 05:06.950 --> 05:09.790 It's some scaffolding, it's specific to crew. 05:10.030 --> 05:16.390 There's definitely a great benefit that this means that you don't have your your various prompts buried 05:16.390 --> 05:18.270 within your code all over the place. 05:18.310 --> 05:22.470 You've got it nicely separated out and you can work on that somewhat independently. 05:22.550 --> 05:26.590 So so I think it's a nice a nice touch in your code. 05:26.590 --> 05:32.080 You can then create something like an agent and instead of specifying all of the fields of an agent. 05:32.080 --> 05:34.160 Like the role of gold backstory. 05:34.160 --> 05:40.160 You can just simply select the configuration as as it shows in this code right here, and they will 05:40.160 --> 05:41.520 all be populated for you. 05:41.840 --> 05:43.840 So it's I like it because it's lightweight. 05:43.840 --> 05:46.000 It's not like there's magic happening behind the scenes. 05:46.000 --> 05:48.320 You clearly refer to the config right there. 05:48.320 --> 05:49.600 It's clear what's going on. 05:49.600 --> 05:55.520 And it has this nice separation of concerns, allowing us to work on our prompts separately from our 05:55.520 --> 05:56.000 code. 05:57.280 --> 06:02.240 And then in addition to the YAML files, there are a couple of Python files. 06:02.240 --> 06:05.640 And the most important one is called crew.py. 06:06.000 --> 06:07.960 And it's where everything comes together. 06:07.960 --> 06:11.640 It defines your crew and it's going to look a bit like this. 06:11.640 --> 06:16.280 And we're going to of course go and look at a proper example in a second, but it has some decorators 06:16.280 --> 06:20.440 over it and you're now you've got a bit of experience with decorators from, from last week. 06:20.640 --> 06:23.760 And uh, sure enough, crew has decorators as well. 06:23.960 --> 06:26.480 And you can see that they there is a few of them. 06:26.480 --> 06:31.840 It has crew base as the decorator you put around the whole class that's going to manage your crew. 06:32.160 --> 06:38.160 And then there's a decorator agent for each of your functions which creates an agent, and there's a 06:38.160 --> 06:42.080 decorator task for each of your functions which creates a task. 06:42.280 --> 06:47.320 And then there's a decorator crew for your final function that generates your crew. 06:47.560 --> 06:54.600 And you can see that it creates an instance of crew, and it returns and it passes in the agents, the 06:54.600 --> 06:55.120 tasks. 06:55.120 --> 06:59.680 And this thing that's telling it that it is sequential, not hierarchical. 06:59.720 --> 07:03.920 It's where you set that important different mode of processing. 07:04.320 --> 07:05.560 And you can see that there. 07:05.560 --> 07:08.600 It says agents is self dot agents. 07:08.760 --> 07:11.640 And you might wonder where is that coming from. 07:11.640 --> 07:18.800 Well that's really one of the roles of this decorator at agent that that is making sure that any function 07:18.800 --> 07:25.320 that has that decorator automatically, the agent that comes from that will be associated with the instance 07:25.320 --> 07:28.080 variable agents will be added to that list. 07:28.080 --> 07:30.840 So that's why you can just simply refer to it at the bottom. 07:31.080 --> 07:35.600 So anyway, this this will be more concrete when we look at a proper coding example. 07:35.640 --> 07:41.080 My main point is that there is this very important module crew, and it's where you define your agents, 07:41.080 --> 07:43.440 tasks and crew, and it uses decorators.