fix: progressive error for write_to_file missing content to break retry loops

[roomote-v0]

Related GitHub Issue

Closes: #11861

Description

This PR attempts to address Issue #11861, adapting the approach from cline/cline#9276 for Roo Code. Feedback and guidance are welcome.

Problem: When the model's output is truncated (due to output token limits or high context usage), write_to_file tool calls arrive with an empty content parameter. The current error handler returns a generic "Missing value for required parameter content. Please retry with complete response." which the model interprets literally and retries identically, creating an infinite retry loop.

Solution: Replace the generic missing parameter error for write_to_file content with a progressive, tiered error message system:

• Tier 1 (first failure): Helpful suggestions -- use apply_diff/edit, break into smaller steps, write a skeleton first
• Tier 2 (second failure): Stronger guidance -- must use a different strategy, do NOT retry full write
• Tier 3 (third+ failure): Critical stop -- do NOT retry write_to_file, required actions listed

The error also includes context window awareness -- when context usage exceeds 50%, the message warns the model that output capacity is reduced.

Changes

• src/core/prompts/responses.ts -- Added writeToFileMissingContentError(relPath, failureCount, contextUsagePercent?) with tiered progressive guidance
• src/core/tools/WriteToFileTool.ts -- Replaced generic sayAndCreateMissingParamError for missing content with the new specialized error, computing context window usage from API metrics
• src/core/prompts/__tests__/writeToFileMissingContentError.spec.ts -- 21 unit tests covering all tiers and context window awareness
• src/core/tools/__tests__/writeToFileTool.spec.ts -- Updated mocks to support the new error path

Test Procedure

cd src && npx vitest run core/prompts/__tests__/writeToFileMissingContentError.spec.ts
cd src && npx vitest run core/tools/__tests__/writeToFileTool.spec.ts

All 45 tests passing (21 new + 24 existing).

Pre-Submission Checklist

• Issue Linked: This PR is linked to an approved GitHub Issue
• Scope: Changes are focused on the linked issue
• Self-Review: I have performed a thorough self-review of my code
• Testing: New and updated tests have been added to cover changes
• Documentation Impact: No documentation updates required
• Contribution Guidelines: I have read and agree to the Contributor Guidelines

Documentation Updates

• No documentation updates are required.

Additional Notes

This adapts the approach from cline/cline#9276 for Roo Code, using Roo's tool names (apply_diff, edit) instead of Cline's (replace_in_file) and integrating with Roo's existing getApiMetrics utility and Task architecture.

Interactively review PR in Roo Code Cloud