ACP multi-file permission requests only display the first file's diff

[alexghergh]

Pre-submission checklist

• I have read the documentation
• I have updated the plugin and all dependencies to the latest versions
• I have searched for existing issues and discussions
• My issue is not a minor or cosmetic quirk (e.g., formatting, spacing, or other non-functional details)

Neovim version (nvim -v)

NVIM v0.11.5

Operating system/version

Fedora Linux Asahi Remix 42

Adapter and model

Codex, any model

Describe the bug

When an ACP agent sends a single permission request containing diffs for multiple files, CodeCompanion currently only displays the first file's edits in the approval UI.

This is a display bug as well as implementation bug. The underlying agent edit still applies changes to all files after approval, but the user only gets to review the first one (even the in chat Proposed edits section only lists the first file only, so all the other file changes are shadow-allowed, meaning the user may never learn about them unless manually inspecting them).

I can think of a couple of ways to fix this:

• In chat, render one Proposed edits for ... section per file, chained one after another, and only issue the Accept / Reject buttons on the last file, or separately after all files have been shown.
• In chat, render a single Proposed edits for ... section for all files, but once the diff shows, the user has the option to go back and forth between file edits (not sure how Accept / Reject would work with this).
• In chat, render a single Proposed edits for ... section for all files, but once the diff shows, the user can only see the first files edits, then upon closing the diff, the second file's edits open the second diff, then upon closing that the third file's edits will show up in a diff etc., chained together. The last file's diff only shows the g2 Accept or reject buttons. Alternatively, the g2 button in a diff that's not the last diff simply says Move to next diff.
• Re-build the diff window to support multi-file inspection + global accept / reject.
• Add buttons for Accept all / Reject all, for multi-file edits. (still, how does the user see all files?)

Because ACP permission is atomic per request, the UI cannot have per-file accept / reject. But it should let the user review all files before making the single global decision.

Note: Titles / summaries for the ACP tool should show Edit 2 files or multiple files if these changes are accepted.

Steps to reproduce

Use an ACP adapter and send a request that proposes edits to two files in one permission request.

For example, ask the agent to edit 2 files in the local directory, at the same time.

E.g. an interaction with Codex:

# User

Can you edit both minimal.lua and README.md files at the same time? Add 'test' at the top of the files.

# Codex

<reasoning>

Edit: minimal.lua

---
**Proposed edits for `minimal.lua`:**

diff
@@ -1,3 +1,4 @@
+-- test
 ---@diagnostic disable: missing-fields
 
 --[[


- `gv` - View
- `g2` - Accept
- `g3` - Reject
- `g4` - Cancel
---

<reasoning>

Added `test` at the top of both files, using syntax-safe comments so `minimal.lua` remains valid.

Expected behavior

The user gets to review both (or multiple) files before deciding on an accept / reject globally.

Screenshots or recordings (optional)

No response

minimal.lua file

---@diagnostic disable: missing-fields

--[[
NOTE: Set the config path to enable the copilot adapter to work.
It will search the following paths for a token:
  - "$CODECOMPANION_TOKEN_PATH/github-copilot/hosts.json"
  - "$CODECOMPANION_TOKEN_PATH/github-copilot/apps.json"
--]]
vim.env["CODECOMPANION_TOKEN_PATH"] = vim.fn.expand("~/.config")

vim.env.LAZY_STDPATH = ".repro"
load(vim.fn.system("curl -s https://raw.githubusercontent.com/folke/lazy.nvim/main/bootstrap.lua"))()

-- Your CodeCompanion setup
local plugins = {
  {
    "olimorris/codecompanion.nvim",
    -- Test with local version (delete if not required)
    -- dir = "~/Code/Neovim/codecompanion.nvim",
    dependencies = {
      { "nvim-lua/plenary.nvim" },
      {
        "nvim-treesitter/nvim-treesitter",
        lazy = false,
        build = ":TSUpdate",
      },

      -- Test with blink.cmp
      {
        "saghen/blink.cmp",
        version = "1.*",
        opts = {
          keymap = {
            preset = "enter",
            ["<S-Tab>"] = { "select_prev", "fallback" },
            ["<Tab>"] = { "select_next", "fallback" },
          },
          cmdline = { sources = { "cmdline" } },
          sources = {
            default = { "lsp", "path", "buffer", "codecompanion" },
          },
        },
      },

      -- Or, test with nvim-cmp
      -- { "hrsh7th/nvim-cmp" },
    },
    opts = {
      --Refer to: https://github.com/olimorris/codecompanion.nvim/blob/main/lua/codecompanion/config.lua
      adapters = {
        acp = {
          codex = function()
            return require("codecompanion.adapters").extend("codex", {
              defaults = {
                auth_method = "chatgpt",
              },
            })
          end,
        },
      },
      interactions = {
        --NOTE: Change the adapter as required
        chat = { adapter = "codex" },
        inline = { adapter = "copilot" },
      },
      opts = {
        log_level = "DEBUG",
      },
    },
  },
}

require("lazy.minit").repro({ spec = plugins })

-- CONFIGURE PLUGINS HERE -----------------------------------------------------

-- Setup Tree-sitter
-- NOTE: Please restart Neovim to ensure parsers are loaded correctly
require("nvim-treesitter")
  .install({
    "lua",
    "markdown",
    "markdown_inline",
    "yaml",
  }, { summary = true, max_jobs = 10 })
  :wait(1800000)

-- Setup nvim-cmp
-- local cmp_status, cmp = pcall(require, "cmp")
-- if cmp_status then
--   cmp.setup({
--     mapping = cmp.mapping.preset.insert({
--       ["<C-b>"] = cmp.mapping.scroll_docs(-4),
--       ["<C-f>"] = cmp.mapping.scroll_docs(4),
--       ["<C-Space>"] = cmp.mapping.complete(),
--       ["<C-e>"] = cmp.mapping.abort(),
--       ["<CR>"] = cmp.mapping.confirm({ select = true }),
--       -- Accept currently selected item. Set `select` to `false` to only confirm explicitly selected items.
--     }),
--   })
-- end

Log output (optional)

No response

Minimal reproduction confirmation

• Yes, I have tested and provided a minimal.lua file that reproduces the issue

[alexghergh]

I'll create a PR once we decide the way forward regarding the diff / proposed edits view.

[olimorris]

This isn't the case with Claude Code.

Sharing my interaction below:

## olimorris

> Context:
> - <tool>memory</tool>
> - <rules>~/.dotfiles/PERSONAL.md</rules>
> - <rules>CLAUDE.md</rules>

Can you edit both minimal.lua and README.md files at the same time? Add 'test' at the top of the files.

## CodeCompanion (Claude Code)

Let me read both files first.

Read: minimal.lua
Read: README.md
Edit: minimal.lua
Edit: README.md

---
**Proposed edits for `minimal.lua`:**

`````diff
@@ -1 +1,2 @@
+test
 ---@diagnostic disable: missing-fields
`````

- `gv` - View
- `g1` - Always accept
- `g2` - Accept
- `g3` - Reject
- `g4` - Cancel
---
The README has multiple occurrences of that string. Let me use more context.

Read: README.md
Edit: README.md

---
**Proposed edits for `README.md`:**

`````diff
@@ -1,3 +1,4 @@
+test
 <!-- panvimdoc-ignore-start -->
 
 <p align="center">
`````

- `gv` - View
- `g1` - Always accept
- `g2` - Accept
- `g3` - Reject
- `g4` - Cancel
---
Done — added `test` at the top of both `minimal.lua` and `README.md`.

which is exactly as Claude Code in the CLI does:

❯ Can you edit both minimal.lua and README.md files at the    
same time? Add 'test' at the top of the files.                
                                                              
⏺ Let me read both files first.                               
                  
  Read 2 files (ctrl+o to expand)                             
                
⏺ Update(minimal.lua)                                         
  ⎿  Added 1 line                       
      1 +test                                                 
      2  ---@diagnostic disable: missing-fields               
      3                                                       
      4  --[[                                                 
                                                              
⏺ Update(README.md)                                           
  ⎿  Error editing file                                       
                                          
⏺ The README has multiple occurrences of that string. Let me
  provide more context to target the first one.               
                                                              
⏺ Update(README.md)                                           
  ⎿  Added 1 line                                             
      1 +test                                                 
      2  <!-- panvimdoc-ignore-start -->                      
      3                                                       
      4  <p align="center">                                   
  ⎿  Found 26 new diagnostic issues in 17 files (ctrl+o to 
     expand)                                     
   
⏺ Done. Added test at the top of both minimal.lua and

Is this a Codex issue?

Edit: Didn't mean to close this

[alexghergh]

I see, I'm afraid those 2 exact files were an unlucky coincidence with Claude Code. It doesn't have to be those 2 files exactly. Could you please ask Claude Code to edit another file then, other than the README.md, together with the minimal.lua? It just has to be a file where that pattern doesn't appear, so it won't complain about multiple occurences of the string and re-check the file. For CLI Claude Code specifically, this issue is not related to that. It is an ACP parsing issue.

The problem is that CodeCompanion's code explicitly only looks at the first file when a requires_diff() event is called, even if the ACP spec says that multiple file edits are possible through a single tool call (the schema for ToolCallUpdate has content as a field, which is an array of ToolCallContent[], here) . The incorrect code inside CodeCompanion is here. The get_diff() method only reads the first file sent by the ACP edit request (i.e. toolCall.content[1], toolCall.locations[1], etc.), even though the array may contain multiple files. I've only checked this with the codex-acp agent, but it should apply to Claude's ACP as well.

Edit: do make sure to run Claude Code in plan mode or something that doesn't let it auto-edit files, since that skips permission request (the path that is broken in get_diff()).

[elebeaup]

@alexghergh Out of curiosity, how does the CLI handle this case when multiple files are edited ?

It might be interesting to replicate that behavior here, to stay consistent with what users are already familiar with

[alexghergh]

For codex I can answer (though I assume claude code is not too different). It prints the diffs inline, e.g.:

• I’ve got the file context. Next edit is minimal: prepend one Lua comment line to the top of both files and leave everything else unchanged.

• Edited 2 files (+2 -0)
  └ ai.lua (+1 -0)
    1 +-- test line
    2  -- Helper Methods

  └ util.lua (+1 -0)
    1 +-- test line
    2  -- wrap nvim-notify's built-in notification position to avoid the cursor,


  Would you like to make the following edits?

  ai.lua (+1 -0)

    1 +-- test line
    2  -- Helper Methods

  util.lua (+1 -0)

    1 +-- test line
    2  -- wrap nvim-notify's built-in notification position to avoid the cursor,

› 1. Yes, proceed (y)
  2. Yes, and don't ask again for these files (a)
  3. No, and tell Codex what to do differently (esc)

As you can see, it shows the diffs for both files (ignore contents, just some personal files) and then has an all-or-nothing approach to the changes (exactly the same as the ACP spec).

Do note that the approach shouldn't necessarily be the same (and probably cannot be the same if there's a diff window in codecompanion), since the actual CLI tools implementations are different from what the ACP protocol does anyway. I agree that we could learn from how the tools work and borrow the design, but I'm not sure how exactly other than inlining diffs, which to me looks much worse than the diff window.

[olimorris]

It's going to be easier if you can share the output from the agent. If you add:

log:debug("[acp::prompt_builder] Permission request for tool call:\n%s", tool_call)

To line 206 in prompt_builder.lua you should see the full tool call (I believe I removed this logging back when I streamlined the performance of CodeCompanion some months back).

In the case of Claude Code and the prompt above, I see:

{
  content = { {
      newText = "test\n---@diagnostic disable: missing-fields",
      oldText = "---@diagnostic disable: missing-fields",
      path = "/Users/Oli/Code/Neovim/codecompanion.nvim/minimal.lua",
      type = "diff"
    } },
  kind = "edit",
  locations = { {
      path = "/Users/Oli/Code/Neovim/codecompanion.nvim/minimal.lua"
    } },
  rawInput = {
    file_path = "/Users/Oli/Code/Neovim/codecompanion.nvim/minimal.lua",
    new_string = "test\n---@diagnostic disable: missing-fields",
    old_string = "---@diagnostic disable: missing-fields",
    replace_all = false
  },
  title = "Edit minimal.lua",
  toolCallId = "toolu_01DaxgFKQrh1Ytn7PzobVgMG"
}

I'll have a think about how we handle this in CodeCompanion.

[alexghergh]

I see. That's very interesting. This looks like it's an ACP agents implementation-related thing then, looks like claude-agent-acp and codex-acp implement their file diffs differently. Looks like codex-acp sends full file replacements (probably out of commodity), while claude-agent-acp only sends targeted edits. However, it still stands that the ACP spec seems to allow this multi-file edit. Did you not manage to get Claude Code to send the edits in the same tool call? The above suggests that only minimal.lua received a file edit, but what happened to the second file edit? Are those sent separately from the ACP agent side?

The tool call I'm getting is full file contents, for both paths (I've truncated for visibility, but the tool call contained full file contents):

{
  content = { {
      newText = "-- test\n---@diagnostic disable: missing-fields\n\n--[[\nNOTE: Set the config path to enable the copilot adapter to work.< ... REST OF THE FILE ...>",
      oldText = "---@diagnostic disable: missing-fields\n\n--[[\nNOTE: Set the config path to enable the copilot adapter to work.< ... REST OF THE FILE ...>",
      path = "/home/alex/.local/share/nvim/lazy/codecompanion.nvim/minimal.lua",
      type = "diff"
    }, {
      newText = "test\n<!-- panvimdoc-ignore-start -->\n\n<p align=\"center\">\n<a href=\"https://codecompanion.olimorris.dev\">< ... REST OF THE FILE ...>",
      oldText = "<!-- panvimdoc-ignore-start -->\n\n<p align=\"center\">\n<a href=\"https://codecompanion.olimorris.dev\">< ... REST OF THE FILE ...>",
      path = "/home/alex/.local/share/nvim/lazy/codecompanion.nvim/README.md",
      type = "diff"
    } },
  kind = "edit",
  locations = { {
      path = "/home/alex/.local/share/nvim/lazy/codecompanion.nvim/minimal.lua"
    }, {
      path = "/home/alex/.local/share/nvim/lazy/codecompanion.nvim/README.md"
    } },
  rawInput = {
    call_id = "call_j1ywDqcCpBN8nx4ID3JXTYgP",
    changes = {
      ["/home/alex/.local/share/nvim/lazy/codecompanion.nvim/README.md"] = {
        move_path = vim.NIL,
        new_content = "test\n<!-- panvimdoc-ignore-start -->\n\n<p align=\"center\">\n<a href=\"https://codecompanion.olimorris.dev\">< ... REST OF THE FILE ...>",
        old_content = "<!-- panvimdoc-ignore-start -->\n\n<p align=\"center\">\n<a href=\"https://codecompanion.olimorris.dev\"> < ... REST OF THE FILE ...>",
        type = "update",
        unified_diff = "@@ -1 +1,2 @@\n+test\n <!-- panvimdoc-ignore-start -->\n@@ -136,2 +137 @@\n <!-- panvimdoc-ignore-end -->\n-\n"
      },
      ["/home/alex/.local/share/nvim/lazy/codecompanion.nvim/minimal.lua"] = {
        move_path = vim.NIL,
        new_content = "-- test\n---@diagnostic disable: missing-fields\n\n--[[\nNOTE: Set the config path to enable the copilot adapter to work.< ... REST OF THE FILE ...>",
        old_content = "---@diagnostic disable: missing-fields\n\n--[[\nNOTE: Set the config path to enable the copilot adapter to work.< ... REST OF THE FILE ...>",
        type = "update",
        unified_diff = "@@ -1 +1,2 @@\n+-- test\n ---@diagnostic disable: missing-fields\n@@ -94,2 +95 @@\n -- end\n-\n"
      }
    },
    turn_id = "019d3952-ddf6-7633-be03-c5f09f012376"
  },
  status = "pending",
  title = "Edit /home/alex/.local/share/nvim/lazy/codecompanion.nvim/minimal.lua, /home/alex/.local/share/nvim/lazy/codecompanion.nvim/README.md",
  toolCallId = "call_j1ywDqcCpBN8nx4ID3JXTYgP"
}

Note that CodeCompanion correctly prints only the unified diff, so from a user perspective, full file contents vs targeted edits are no different. Just the single file vs multi-file is a real bug.

Edit: It does look like Claude Code itself is single-file only edits, and it queues files one by one separately. This seems to be reflected in the implementation of claude-agent-acp. Codex on the other hand allows multiple file edits.

[olimorris]

Did you not manage to get Claude Code to send the edits in the same tool call? The above suggests that only minimal.lua received a file edit

It came through in a separate edit. Claude Code does indeed do this as separate edits.

So it looks like Codex is essentially bundling multiple file edits as one tool call. Meaning that you either accept-all or reject-all?

I've not built the diff logic to handle this so will think what the best UX is for this.