fix(agents): stop dropping self-paired tool messages during sanitation

[Osamaali313]

Description

When a model request contains an unpaired tool block, _sanitize_tool_messages runs _reorder_tool_results + _remove_unpaired_tool_messages to repair ordering/pairing. In that path, a valid AgentScope 2.0 self-paired assistant message — one that carries its own tool_call and matching tool_result in the same Msg ([text, tool_call, tool_result]) — was silently dropped, losing the text and the whole turn from the request sent to the model.

Root cause (two functions):

• _reorder_tool_results treated every result-bearing message as a movable result-carrier, skipping it to re-insert after a tool_call in another message; for a self-paired message the call is in the same (skipped) message, so it was never re-inserted.
• _remove_unpaired_tool_messages only scanned following messages for a tool_call's results, so a self-paired message's own tool_result never satisfied its own use and the message was judged unpaired.

Fix: keep messages that carry their own tool_call in place during reordering; satisfy a message's tool_calls from its own tool_results first (and don't consume a following self-paired message as a result provider); and let a message's own tool_calls pair its own tool_results in the final sweep.

Type of Change

• Bug fix (non-breaking change which fixes an issue)

Component(s) Affected

• Core (src/qwenpaw/agents/utils/tool_message_utils.py)
• Tests

Checklist

• Run and pass pre-commit run --all-files (on the changed files — see evidence)
• Run and pass relevant tests (pytest)
• No documentation change needed (internal sanitation helper)

Testing

Added TestSanitizeToolMessages::test_self_paired_message_kept_when_another_block_unpaired: a batch with an unrelated unpaired tool_call plus a valid self-paired [text, tool_call, tool_result] message. Before the fix the self-paired message is dropped; after, it is preserved (and the unpaired orphan is still removed). Classic separate tool_call/tool_result pairs, result-before-call reordering, and orphan removal remain unchanged.

Local Verification Evidence

$ pre-commit run --files src/qwenpaw/agents/utils/tool_message_utils.py tests/unit/agents/utils/test_tool_message_utils.py
check python ast.........................................................Passed
check docstring is first.................................................Passed
fix python encoding pragma...............................................Passed
detect private key.......................................................Passed
trim trailing whitespace.................................................Passed
Add trailing commas......................................................Passed
mypy.....................................................................Passed
black....................................................................Passed
flake8...................................................................Passed
pylint...................................................................Passed
(yaml/xml/toml/json/prettier: no matching files -> Skipped)

$ pytest tests/unit/agents/utils/test_tool_message_utils.py tests/unit/agents/test_message_request_normalizer.py -q
71 passed

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.

[github-actions]

Welcome to QwenPaw! 🐾

Hi @Osamaali313, thank you for your first Pull Request! 🎉

📋 About PR Template

To help maintainers review your PR faster, please make sure to include:

• ✅ Description - What this PR does and why
• ✅ Type of Change - Bug fix / Feature / Breaking change / Documentation / Refactoring
• ✅ Component(s) Affected - Core / Console / Channels / Skills / CLI / Documentation / Tests / CI/CD / Scripts
• ✅ Checklist:
  • Run and pass pre-commit run --all-files
  • Run and pass relevant tests (pytest or as applicable)
  • Update documentation if needed
• ✅ Testing - How to test these changes
• ✅ Local Verification Evidence:

  pre-commit run --all-files
  # paste summary result
  
  pytest
  # paste summary result

Complete PR information helps speed up the review process. You can edit the PR description to add these details.

🙌 Join Developer Community

Thanks so much for your contribution! We'd love to invite you to join the official QwenPaw developer group! You can find the Discord and DingTalk group links under the "Developer Community" section on our docs page:
https://qwenpaw.agentscope.io/docs/community

We truly appreciate your enthusiasm—and look forward to your future contributions! 😊

We'll review your PR soon.

---

Tip

⭐ If you find QwenPaw useful, please give us a Star!

Staying ahead

Star QwenPaw on GitHub and be instantly notified of new releases.

Your star helps more developers discover this project! 🐾

[qbc2016]

LGTM.

[github-actions]

Welcome to QwenPaw! 🎉

Thank you @Osamaali313 for your first contribution! Your PR has been merged. 🚀

We'd love to give you a shout-out in our release notes! If you're comfortable sharing, please reply to this comment with your social media handles using the format below:

discord: your_discord_handle
x: your_x_handle
xiaohongshu: your_xiaohongshu_id

Note: Only share what you're comfortable with — all fields are optional.

Thanks again for helping make QwenPaw better!

[Osamaali313]

Thanks so much, and glad it landed! 🎉 Happy to be shouted out — here are the handles I'm comfortable sharing:

x: @OsamaAli_72 (https://x.com/OsamaAli_72)
github: Osamaali313 (https://github.com/Osamaali313)
linkedin: https://www.linkedin.com/in/syedosamaali72
instagram: https://www.instagram.com/osamaali_72

(No Discord/Xiaohongshu.) Thanks again — looking forward to contributing more!