[I work on Claude Code] I broadly agree with the author’s point: plan mode was useful, and is no longer useful.
In Claude Code, all plan mode does is add a little reminder to every user message along the lines of “you’re in plan mode, please don’t code yet”. It’s something I came up with late on a Sunday night many months ago, when I got tired of asking Claude to plan with me first before coding in each new session. Something people might not realize is plan mode has always been a prompt — it has never changed the toolset because doing so would break the prompt cache, and so would be expensive for users.
This worked well for a while, until a few months ago, using early versions of Fable, I realized that I wasn’t using plan mode anymore because the model just got it, and because for the increasingly complex work I asked the model to do, planning had become interactive and iterative. With Opus 5.5, I feel Opus has gotten to that point too.
For codebase understanding, I sometimes ask Claude to generate an artifact that explains some aspect of its changes. For complex diffs to core parts of the system, I will often ask it to make diagrams or even interactive demos so I can better understand the change and alternatives considered. I don’t do this very often, but it’s a useful way to explain code when you need it. I ask Claude to attach these artifacts to its PRs also, so others can understand and future Claudes have the context.
I use plan mode, because my current project benefits from "pair programming."
I have one session define a task, and provide a formal specification plus context in a "cover letter."
The session B, in plan mode, produces the plan back.
Session one reviews the plan and clears it, ratifying portions and often specifying specific changes.
Session one then executes.
What has been striking to me in this approach is that even with two instances of the same model (currently Opus 5.5), there are regularly corrections made. I use "project chat" for session A and Code for session B atm; it is very typical that Code finds and corrects details or oversights in the task spec; it is also typical (though less so with 5.5) that session A (chat) pushes back or clarifies things Code doesn't have the context for.
I have been afraid to open up the potential of negotiation beyond what this is costing as it is. But I am also afraid to simply skip the formalisms, because of the consistent correction that occurs in this back-and-forth.
Each component of the pattern is schematized, generated from a template, and validated, to keep things tight.
Lots of tokens! But I trust this process far more than "just typing" :)
bcherny · · focus · HN ↗
In Claude Code, all plan mode does is add a little reminder to every user message along the lines of “you’re in plan mode, please don’t code yet”. It’s something I came up with late on a Sunday night many months ago, when I got tired of asking Claude to plan with me first before coding in each new session. Something people might not realize is plan mode has always been a prompt — it has never changed the toolset because doing so would break the prompt cache, and so would be expensive for users.
This worked well for a while, until a few months ago, using early versions of Fable, I realized that I wasn’t using plan mode anymore because the model just got it, and because for the increasingly complex work I asked the model to do, planning had become interactive and iterative. With Opus 5.5, I feel Opus has gotten to that point too.
For codebase understanding, I sometimes ask Claude to generate an artifact that explains some aspect of its changes. For complex diffs to core parts of the system, I will often ask it to make diagrams or even interactive demos so I can better understand the change and alternatives considered. I don’t do this very often, but it’s a useful way to explain code when you need it. I ask Claude to attach these artifacts to its PRs also, so others can understand and future Claudes have the context.
aaroninsf · · focus · HN ↗
I have one session define a task, and provide a formal specification plus context in a "cover letter."
The session B, in plan mode, produces the plan back.
Session one reviews the plan and clears it, ratifying portions and often specifying specific changes.
Session one then executes.
What has been striking to me in this approach is that even with two instances of the same model (currently Opus 5.5), there are regularly corrections made. I use "project chat" for session A and Code for session B atm; it is very typical that Code finds and corrects details or oversights in the task spec; it is also typical (though less so with 5.5) that session A (chat) pushes back or clarifies things Code doesn't have the context for.
I have been afraid to open up the potential of negotiation beyond what this is costing as it is. But I am also afraid to simply skip the formalisms, because of the consistent correction that occurs in this back-and-forth.
Each component of the pattern is schematized, generated from a template, and validated, to keep things tight.
Lots of tokens! But I trust this process far more than "just typing" :)