> I often hear people use the words agent and model interchangeably
_what_ people. Would I hear one of my colleagues do this, I'll slap them across the face. With a 4 pounds salmon. Alive.
> to help us have more precise conversations.
What problem are you trying to solve. _Why_ you need more precise conversations.
I mean, I understand what you aiming at. But is it really worth it to go nitpicking at people's mental models, is the gain worth it?
You can argue that the model has access to that tool through the harness the same way your brain has access to see this comment through your body (your eyes specifically).
Sure, but given the situation and audience of this talk, I think they should be more precise with how they word these things. If you watch the video you'll see what I mean. He talks like they have no control over what they give to the model, because the model simply "has access" by default, which is not true.
Well first off if you ask Microsoft everything is Copilot.
Secondly the confusion is designed to benefit the bull** by using ambiguous language they can do as humpty dumpty did in Alice in Wonderland and say "When I use a word, it means just what I choose it to mean. Neither more nor less"
Which benefits whatever they are pushing.
Beware those that attempt to muddle language and had precision in speaking.
Why "layers"? The constituents of a Multi-agent System (MAS) [1] are called "agents". BTW: Synecdochical semantic diffusion is not uncommon in software engineering
Real-life usage of interchangeable or synecdochical word triumphs in real life.
My take on the post is for engineering disciple where JoeJag wants to create a common word while tackling "Agent" issues.
I like Joe's approach as this disambiguates during troubleshooting without trying to figure out under which "context" other engineers are using Agent vs. Models.
You get lost in context just like AIs do without such disambiguation.
I've literally never heard anyone conflate an agent and a model. Ever.
Often with posts like this I imagine someone had their own confusion and then somehow projected it on everyone else. Like Trump thinking people didn't know about the word groceries or that dumb ends with a b.
> I've literally never heard anyone conflate an agent and a model. Ever.
Author is a senior staff engineer. A big part of his job is to help more junior engineers and non-technical decision makers understand basics. Not every stakeholder with resources reads HN under a pseudo name "llm_nerd" :)
And to be fair to those juniors and less-technical folks: there were papers in prominent ML conferences up to like 2024-2025 that were consistently comparing proprietary model end-points to open weight models as an apples-apples comparison until very recently, and long after it was obvious that prop model providers were doing "stuff" behind the endpoint, and without putting in the legwork to figure out if/when that "stuff" was happening, or what the "stuff" probably was, or even adding a caveat. Not exactly the same thing, but definitely 100% conflating "model+software" with "model".
I have—frequently—especially among the non-technical crowd.
For example, the recent-ish OpenAI Hugging Face breakout was widely reported as a rogue model escaping. But a model on its own can’t do anything—it’s the agent/harness that escaped. I think it’s an important distinction and I’m glad to see efforts attempting to clear it up.
>But a model on its own can’t do anything—it’s the agent/harness that escaped
An agent/harness "can't do anything" on its own either, so how is saying "an agent escaped" somehow accurate? People talked about the model because it was the model that made the difference. It was specifically the differentiating factor.
I knew this would turn into a super boring thing where people will announce that they too misunderstood, therefore everyone does, but this is all very silly nonsense.
> I knew this would turn into a super boring thing where people will announce that they too misunderstood, therefore everyone does, but this is all very silly nonsense.
I don't understand. You said:
> I've literally never heard anyone conflate an agent and a model. Ever.
but when people give you counterexamples suddenly anecdotal experience is boring and silly nonsense?
> I've literally never heard anyone conflate an agent and a model. Ever.
I recently had to explain it to my brother, who works as a programmer but doesn't read much about technology beyond documentation that solves his immediate problem. (Before anyone comments on whether that attitude is wise: not the point of my comment, and also, this is the reality of how many programmers operate, like it or not).
> I've literally never heard anyone conflate an agent and a model. Ever.
That's because you know enough to disambiguate on the fly, which isn't true for the majority of the population. In other words, you make assumptions about others based on your own condition.
The concern here isn't that someone doesn't know what they're talking about, it's that many of those listening can be misled by the ambiguous wording of people who know very well what they are doing and can even do it deliberately.
> Like Trump thinking people didn't know about the word groceries or that dumb ends with a b.
Again, you're using yourself as source of assumptions about his audience, and worse, you transfer that to a much more complicated subject with unsettled terminology.
The post ends with a comment on "its not about being pedantic..." so, a few not being pedantic bits:
In the table "Real world examples";
"Claude Desktop" houses three harnesses at the moment; Claude, Claude Cowork, and Claude Code.
"Claude CLI", I presume, is referring to Claude Code CLI. This is distinct from the 'ant CLI', which is sometimes referred to as 'Claude CLI'.
"Cursor" could be any of them- but, 'Cursor Agents', 'Cursor Cloud Agents', 'Cursor CLI', and whatever the vscode fork is called now, are distinct. Maybe not in the context of this blog post, but it isnt specified which is being referred to in the example table.
"ChatGPT" sounds like the chatgpt web interface. OpenAI's desktop app is named 'ChatGPT Desktop', and now houses 'ChatGPT work' and 'Codex' (Codex Desktop, not the TUI, though it does essentially wrap the tui and give it capabilities through app-built-in tools). I believe the ChatGPT web interface's harness can change a bit, depending on settings + subscription level (remote sandboxes, etc.) Additionally, there is a distinction in available models depending on which "ChatGPT" product is being used (instant/live/etc non-5.6 luna/terra/sol suite).
Inference service is more accurately 'default inference provider'.
If the goal is to provide a distinction between model and agent, i think the "agent system" is doing too much heavy lifting in the example here.
A useful extension to this mental framework that i use when trying to make this distinction is the application (cursor) -> which sometimes includes an orchestrator and all of the QOL stuff like resuming, checkpointing, etc. single or multiple agents (cursor agents)-> and runs a single or many agent instances (single agent in cursor)-> service api-> model.
This is to address a confusion i often see with agent being conflated with the application that we use agents in, rather than the distinction in the article which tries to unpick agent-model confusion.
A fun one is that in claude code, you can configure 'agents' which are prompt presets + some configuration. Or sub-agents sometime are indistinguishable from the foreground agent (usually called orchestrator) in configuration except that they have different contents in their context window (forks more or less).
IMO, if there's a ubiquitous term that is unambiguous, use it (harness, model). If there's an ambiguous term you have to explain, try not to use it. Language is for communication.
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[ 0.24 ms ] story [ 6.8 ms ] thread> I often hear people use the words agent and model interchangeably
_what_ people. Would I hear one of my colleagues do this, I'll slap them across the face. With a 4 pounds salmon. Alive.
> to help us have more precise conversations.
What problem are you trying to solve. _Why_ you need more precise conversations. I mean, I understand what you aiming at. But is it really worth it to go nitpicking at people's mental models, is the gain worth it?
Eric from alignment and research at OpenAI: https://www.youtube.com/watch?v=87DyyMV0kCY
It honestly bothers me so much when he says "This new model has access to x". No, the harness you allowed it use at runtime has access to x.
Secondly the confusion is designed to benefit the bull** by using ambiguous language they can do as humpty dumpty did in Alice in Wonderland and say "When I use a word, it means just what I choose it to mean. Neither more nor less" Which benefits whatever they are pushing.
Beware those that attempt to muddle language and had precision in speaking.
Why "layers"? The constituents of a Multi-agent System (MAS) [1] are called "agents". BTW: Synecdochical semantic diffusion is not uncommon in software engineering
[1] https://en.wikipedia.org/wiki/Multi-agent_system
My take on the post is for engineering disciple where JoeJag wants to create a common word while tackling "Agent" issues.
I like Joe's approach as this disambiguates during troubleshooting without trying to figure out under which "context" other engineers are using Agent vs. Models.
You get lost in context just like AIs do without such disambiguation.
Often with posts like this I imagine someone had their own confusion and then somehow projected it on everyone else. Like Trump thinking people didn't know about the word groceries or that dumb ends with a b.
Author is a senior staff engineer. A big part of his job is to help more junior engineers and non-technical decision makers understand basics. Not every stakeholder with resources reads HN under a pseudo name "llm_nerd" :)
And to be fair to those juniors and less-technical folks: there were papers in prominent ML conferences up to like 2024-2025 that were consistently comparing proprietary model end-points to open weight models as an apples-apples comparison until very recently, and long after it was obvious that prop model providers were doing "stuff" behind the endpoint, and without putting in the legwork to figure out if/when that "stuff" was happening, or what the "stuff" probably was, or even adding a caveat. Not exactly the same thing, but definitely 100% conflating "model+software" with "model".
For example, the recent-ish OpenAI Hugging Face breakout was widely reported as a rogue model escaping. But a model on its own can’t do anything—it’s the agent/harness that escaped. I think it’s an important distinction and I’m glad to see efforts attempting to clear it up.
An agent/harness "can't do anything" on its own either, so how is saying "an agent escaped" somehow accurate? People talked about the model because it was the model that made the difference. It was specifically the differentiating factor.
I knew this would turn into a super boring thing where people will announce that they too misunderstood, therefore everyone does, but this is all very silly nonsense.
I don't understand. You said:
> I've literally never heard anyone conflate an agent and a model. Ever.
but when people give you counterexamples suddenly anecdotal experience is boring and silly nonsense?
I recently had to explain it to my brother, who works as a programmer but doesn't read much about technology beyond documentation that solves his immediate problem. (Before anyone comments on whether that attitude is wise: not the point of my comment, and also, this is the reality of how many programmers operate, like it or not).
That's because you know enough to disambiguate on the fly, which isn't true for the majority of the population. In other words, you make assumptions about others based on your own condition.
The concern here isn't that someone doesn't know what they're talking about, it's that many of those listening can be misled by the ambiguous wording of people who know very well what they are doing and can even do it deliberately.
> Like Trump thinking people didn't know about the word groceries or that dumb ends with a b.
Again, you're using yourself as source of assumptions about his audience, and worse, you transfer that to a much more complicated subject with unsettled terminology.
In the table "Real world examples";
"Claude Desktop" houses three harnesses at the moment; Claude, Claude Cowork, and Claude Code.
"Claude CLI", I presume, is referring to Claude Code CLI. This is distinct from the 'ant CLI', which is sometimes referred to as 'Claude CLI'.
"Cursor" could be any of them- but, 'Cursor Agents', 'Cursor Cloud Agents', 'Cursor CLI', and whatever the vscode fork is called now, are distinct. Maybe not in the context of this blog post, but it isnt specified which is being referred to in the example table.
"ChatGPT" sounds like the chatgpt web interface. OpenAI's desktop app is named 'ChatGPT Desktop', and now houses 'ChatGPT work' and 'Codex' (Codex Desktop, not the TUI, though it does essentially wrap the tui and give it capabilities through app-built-in tools). I believe the ChatGPT web interface's harness can change a bit, depending on settings + subscription level (remote sandboxes, etc.) Additionally, there is a distinction in available models depending on which "ChatGPT" product is being used (instant/live/etc non-5.6 luna/terra/sol suite).
Inference service is more accurately 'default inference provider'.
Also, this post has an ai-generated smell.
A useful extension to this mental framework that i use when trying to make this distinction is the application (cursor) -> which sometimes includes an orchestrator and all of the QOL stuff like resuming, checkpointing, etc. single or multiple agents (cursor agents)-> and runs a single or many agent instances (single agent in cursor)-> service api-> model.
This is to address a confusion i often see with agent being conflated with the application that we use agents in, rather than the distinction in the article which tries to unpick agent-model confusion.
IMO, if there's a ubiquitous term that is unambiguous, use it (harness, model). If there's an ambiguous term you have to explain, try not to use it. Language is for communication.