External Agents do not allow editing of previous messages (Unavailable Editing)

[foxx]

Body

What are you proposing?

Ability to edit previous messages when using External Agents.

With the exception of the Zed agent itself, editing previous messages shows a tooltip that says "Unavailable Editing - Editing previous messages is not available yet.

Why does this matter?

Being able to just jump back in the conversation and pivot from that point is quite a nice developer experience. It would be even nicer if there was a graph based branching approach, but that is well outside the scope of this issue. I've raised this issue specifically because I couldn't find any other issues that explain why the external agents don't allow editing of previous messages and whether that's a problem with ACP, Zed or the agents themselves.

Are there any examples or context?

This seems to apply to all of the external agents, or at least the ones I've tested, which are:

• Claude Agent
• Codex CLI
• Corust Agent Cursor
• Gemini CLI
• OpenCode

Possible approach

I'm sure this is probably already documented somewhere. I just couldn't find it. As a possible approach, just having clarification on what is required to get this working so that it's clear for anyone else wondering about this.

Or even a little message inside the tooltip itself giving a brief explanation (e.g. "this isn't our fault, go nag {project} for {feature}") etc.

[samholmes]

The External Agent integration (ACP) is the main selling point for me to switch to Zed as my daily driver, however seeing a caveat like this is going to be an annoyance to deal with and perhaps deter a lot of user acquisition like myself.

If Zed can focus on making the External Agents (ACP) work so flawless and seamlessly, then Zed will be very successful in capturing a huge market of people that use many harnesses because Zed could be the one agent tool where all the harnesses are in one place.

Capturing the user's to use Zed as the UI could position Zed well in the AI industry to steer them to Zed features of course and that's the business model... Just sayin'.

[fr0der1c]

Being able to use /side to ask questions and edit previous messages has been an important part of my daily development flow. I really need this feature. For now, I'll stick to using the Codex CLI in the terminal rather than external agents in Zed.

[carloscheddar]

This is the main feature blocking me from making Zed my main editor. Being able to edit or go back X amount of messages like you can do in Cursor is a feature I use daily.

[abhishek47kashyap]

Would be great to see this prioritized! I've lost count of how many times I've made the silly error of typing "not that" instead of "note that", and for all I know the thread has been polluted with that unintentional "not".

A less grievous error I also tend to make is hitting the Enter key instead of + key (numpad all the way on the right of a keyboard) and that sends an incomplete message to the agent. This can be rectified by typing out the full message immediately after and re-sending it, but being able to edit a previous message would be helpful here too.

[Flamintus]

For me this is a must-have. In daily use, it's very common to want to edit a message after sending it — especially when you realize the model's answer is off-target, which is often caused by how the question was phrased. Same goes for typos and accidental Enter presses.

This is actually one of the few reasons why I still haven't switched my daily chat from the Claude Code CLI to Zed.

I'm also starting to worry when I see threads this old still sitting as discussions, while I consider this capability essential.

[NewtonChutney]

yeahh, I've been hooking up claude models directly via Vertex APIs to the zed agent for that reason..
In the zed agent, we at least can edit past msgs

[NewtonChutney]

We might be getting there? 👀
https://agentclientprotocol.com/protocol/v2/migration#session/update-variant-changes

[NewtonChutney]

https://agentclientprotocol.com/protocol/v2/migration#whole-message-upserts

Use chunks for streaming. Use whole-message updates for replay, correction, or output that is already complete.

[erikdemarco]

when it will be released?

[nickwang0808]

I would consider this as a high priority as well, tools like Paseo has it implemented using ACP, and it's eating up Zed's market share. Zed could totally be the agent native tool if it has these features implemented

[jjhidalgar-celonis]

Agree, this is a must for any serious coding

[VitroidFPV]

Came back to Zed after a while and I was surprised this wasn't already a thing 😅 This would be a great feature that's standard in many other tools.

[gmatev]

Definitely would be a huge quality of life improvement