[Bug]: Desktop GUI: Drag-and-drop image upload freezes the UI

[RodelRobel]

Bug Description

Dragging an image into the chat input area in 'hermes desktop' causes the UI to freeze completely with no response.
Contrast: Manually pasting a file path (e.g. 'C:\Users\Administrator\Desktop\Lattice.png') works fine — 'vision_analyze' is called as a tool and the image is recognized correctly.
Main model: deepseek-v4-pro
Vision model: qwen3.5-plus (auxiliary)

Steps to Reproduce

1. Launch 'hermes desktop'
2. Drag any '.png' / '.jpg' image from File Explorer into the chat window
3. UI freezes

Expected Behavior

It should read the picture with vision model and give response

Actual Behavior

The UI freeze(maybe with main model which do not have visual ability like deepseek)

Core error — vision model API incompatibility (resolved via image_routing)

2026-07-13 16:02:05,831 ERROR tools.vision_tools: Error analyzing image: 
Error code: 400 - {'error': {'message': 
"Failed to deserialize the JSON body into the target type: 
messages[0]: unknown variant `image_url`, expected `text` at line 1 column 56187", 
'type': 'invalid_request_error', 'param': None, 'code': 'invalid_request_error'}}

Traceback:
  File "tools/vision_tools.py", line 1253, in vision_analyze_tool
  File "agent/auxiliary_client.py", line 7431, in async_call_llm
  ...
openai.BadRequestError: Error code: 400 - 
  messages[0]: unknown variant `image_url`, expected `text`

### Affected Component

Agent Core (conversation loop, context compression, memory)

### Messaging Platform (if gateway-related)

_No response_

### Debug Report

```shell
Report       https://dpaste.com/8JSFCV7HG
agent.log    https://dpaste.com/HB3GA3XJS
gui.log      https://paste.rs/SsExo
desktop.log  https://paste.rs/KCKSG

Operating System

Windows 10

Python Version

No response

Hermes Version

0.18.2

Additional Logs / Traceback (optional)

Root Cause Analysis (optional)

No response

Proposed Fix (optional)

1. When a file is dropped, obtain the file's local absolute path
2. Send the path as plain text over WebSocket to the backend (e.g. C:\Users\...\xxx.png)
3. The backend's _detect_file_drop() will automatically detect, resolve, and route it to the correct image processing pipeline
4. Currently, the GUI layer may be attempting to read and send the file content (base64-encoded), causing the freeze

Are you willing to submit a PR for this?

• I'd like to fix this myself and submit a PR

[GottZ]

This was generated by AI during triage.

Summary

One PR addresses #63682. #66546 removes the reported Windows Explorer drag-and-drop freeze path by using object URLs for in-hand image files instead of synchronously reading and base64-encoding them over IPC, while retaining the existing path-based attachment pipeline.

Related pull requests

• fix(desktop): avoid Explorer DnD image preview freeze on Windows #66546 best fix — (+335/-20) — best fix, keep open pending lifecycle completion: the diff directly avoids the freeze-causing IPC/base64 preview path for Explorer drops and adds direct-submit and queue ownership handoffs. However, consistent with the contributor's keep_open review on fix(desktop): avoid Explorer DnD image preview freeze on Windows #66546, the visible production diff retains blob URLs through final optimistic-submit handoffs but does not show a production consumer that revokes them when the optimistic message is discarded or replaced; the test only performs that final revocation manually.

Suggested consolidation

Keep #66546 as the consolidation target and merge it after adding and testing production-side revocation when the final optimistic submit consumer is discarded or replaced. It is the only PR and the verified best fix for the reported freeze, but the visible diff does not yet fully resolve the contributor's blocking blob-URL ownership concern; there are no duplicate PRs to close.

Complex graph

flowchart LR
    classDef open fill:#dbeafe,stroke:#1d4ed8,color:#1e3a8a
    classDef merged fill:#dcfce7,stroke:#15803d,color:#14532d
    classDef closed fill:#e5e7eb,stroke:#6b7280,color:#1f2937
    classDef unverified fill:#f3f4f6,stroke:#9ca3af,color:#374151
    classDef best stroke-width:3px,stroke:#b45309
    classDef target stroke-width:3px,stroke:#4338ca
    I63682(["issue #63682 (open)"])
    P66546["PR #66546 (open)"]
    P66546 -->|best fix| I63682
    class I63682 open
    class I63682 target
    class P66546 open
    class P66546 best
    click I63682 "https://github.com/NousResearch/hermes-agent/issues/63682"
    click P66546 "https://github.com/NousResearch/hermes-agent/pull/66546"

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Graph: solid arrow = fixes / best fix, dashed arrow = partial or unverified (see edge label); boxed group = PRs duplicating each other; amber border = best fix; indigo border = target; gray node = closed or no verify verdict yet (state tag in the node label).

Cross-PR triage: Reviewed 1 pull request and 1 issue in this complex. Each diff was read against this issue; Assessment working set: 24 kB of PR diffs, 6 kB of issue/PR text, 2 kB of discussion (2 comments), 2 verify verdicts. verdicts reflect diff content, not PR titles. Part of an automated triage batch.