[BUG] new read_file tool bug

[mini2s]

Problem (one or two sentences)

Not protecting against context window overflow when reading a large number of files may result in an error message during the first conversation

Context (who is affected and when)

Not protecting against context window overflow when reading a large number of files may result in an error message during the first conversation

Reproduction steps

The user's first conversation resulted in a context explosion when reading a directory containing many large files

Expected result

Ensure that the conversation does not report errors on the first attempt

Actual result

The user's first conversation resulted in a context explosion when reading a directory containing many large files

Variations tried (optional)

No response

App Version

latest

API Provider (optional)

None

Model Used (optional)

No response

Roo Code Task Links (optional)

No response

Relevant logs or errors (optional)

[roomote]

I'd like to help with this issue, but I need some clarification to ensure I implement the right solution. Could you please provide more details on the following:

1. Error message: What specific error message or behavior are you seeing? Is it an API error from the provider (e.g., "context length exceeded") or an application-level error?

2. Reproduction scenario: How exactly did this occur? For example:

   • Did you mention a directory path (like @folder) in your prompt, causing the agent to read many files?
   • Did the agent decide to call read_file multiple times on its own?
   • Was it a single large file, or multiple files?

3. Model and provider: Which API provider and model were you using? Different models have different context windows, which affects when overflow occurs.

4. First conversation context: You mention "first conversation" - does this mean the very first message/turn in a new task, before any context was accumulated from previous turns?

5. Expected behavior: What behavior would you expect? For example:

   • Should the tool proactively check context budget before reading?
   • Should there be a limit on how many files can be read at once?
   • Should files be automatically truncated more aggressively?

Understanding these details will help me propose the right solution. Please tag @roomote in your response with the answers, and I'll be happy to propose an implementation plan.

[mini2s]

@roomote

Did you mention a directory path (like ) in your prompt, causing the agent to read many files?

use @folder

Did the agent decide to call multiple times on its own?

use read_file

Was it a single large file, or multiple files?

yes

[roomote]

Thanks for the clarification! I understand now that the issue occurs when:

1. Using @folder to reference a directory
2. The agent calls read_file multiple times to read the files in that folder
3. This causes a context window overflow error on the first conversation

I'll explore a potential fix to protect against context window overflow when reading multiple files. I'll open a PR to share progress.

[roomote]

Opened a PR with my attempt at addressing this issue: #11138

Summary of changes:

• Added MAX_FOLDER_FILES_TO_READ (10 files) limit for folder mentions
• Added MAX_FOLDER_CONTENT_SIZE (100KB) limit for total content size
• When limits are reached, users get informative messages suggesting to use individual @file mentions instead

Feedback welcome!