Bug: WriteFile tool fails with missing file_path parameter when creating large HTML files

[pomelo-nwu]

Bug Description

When attempting to create a large HTML file using the WriteFile tool, the tool fails with the following error:

```
params must have required property 'file_path'
Note: Your previous response was truncated due to max_tokens limit, which likely caused incomplete tool call parameters.
```

Steps to Reproduce

1. Use the WriteFile tool to create a large HTML file (landing page with extensive CSS and JavaScript)
2. The tool call gets truncated due to max_tokens limit
3. The file_path parameter is not properly included in the tool call

Expected Behavior

The WriteFile tool should successfully create the file with all provided content.

Actual Behavior

The tool call is truncated, resulting in missing required parameters.

Workaround

The file was eventually created successfully on the second attempt:
```
✓ WriteFile Writing to landing.html
```

Environment

• Tool: Qwen Code CLI
• File type: HTML (landing page)
• Content size: Large (includes full CSS styles and JavaScript)

Additional Context

This appears to be related to response token limits when creating files with extensive content. The content included:

• Full HTML5 document structure
• Embedded CSS (500+ lines)
• JavaScript for animations and interactivity
• Code rain canvas animation

Consider implementing chunked file writing or increasing token limits for large file creation operations.

[yiliang114]

Linking a few related threads for context:

• 长期出现缺少参数的现象，包括但不限于writefile、shell，参数不限于 file_path、content、command #2783 reports the same class of symptom: tool calls occasionally arrive with missing required params such as file_path, content, or command.
• Tool calls with edits/write fail when using Qwen3 30b in 0.0.10 #535 is an older write/edit failure report with similar missing-parameter behavior in file tools under a specific model setup.
• fix: max_tokens not auto-detected for non-Qwen models, causing response truncation #2358 is relevant background on response truncation causing incomplete tool call payloads. That issue is closed, but the failure mode is related.
• fix: detect and protect against truncated tool call output #2021 added protection against truncated tool call output.
• feat(core): adaptive output token escalation (8K default + 64K retry) #2898 added adaptive output token escalation (8K -> 64K) to reduce truncation-related failures.

Keeping this one separate for now because it includes a more concrete repro around a large single-shot WriteFile HTML payload, which may make it easier to validate against current behavior.

[kilyabin]

i have same issue with ReadFile

  ✦ The tool requires a file_path parameter. Let me read the payment.py file to see the existing upload-proof endpoint.
 x  ReadFile {"absolute_path":"CENSORED"}                                                                                                                                                                                                                                 
  params must have required property 'file_path'