Downstream tool node unable to access tool file provided by upstream tool

[Donchka]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

I create two tool plugin myself and try to integrate them into my workflow. The upstream tool has a file as its output.

However, when I try to use this file as the input of my downstream tool, I got the following error "Failed to rectify image: Invalid file URL '/files/tools/585bcff5-6de7-4792-9c71-bbce791c6097.webp?...': Request URL is missing an 'http://' or 'https://' protocol.. Ensure the FILES_URL environment variable is set in your .env file". If I use the file from user input node as input for downstream tool, it will run smoothly without any issues. The tool reads blob from tool_parameters. I am expecting the same behaviour for upstream tool files.

Much appreciated if anyone could help me with this issue!

2. Additional context or comments

No response

[dosubot[bot]]

Hi @Donchka! I'm Dosu and I’m helping the dify team.

This is a known issue caused by the FILES_URL environment variable not being properly configured. When it's empty or misconfigured, Dify generates file URLs as relative paths (/files/tools/...) instead of full URLs with the protocol prefix.

Solution: Set FILES_URL in your .env file with the full protocol:

FILES_URL=http://192.168.x.x:5001

For Docker Compose setups (Dify 1.11.4+), you may also need to configure:

• INTERNAL_FILES_URL=http://api:5001 — for internal container-to-container communication
• FILES_URL=http://your-external-ip:port — for external access

Important notes:

• Don't use localhost in Docker environments — use your actual intranet IP address
• Ensure port 5001 is exposed in your docker-compose.yaml with ports: - "5001:5001"

After updating, restart your services:

docker-compose down && docker-compose up -d

This should make upstream tool file outputs work the same way as user input files in your downstream tools.

To reply, just mention @dosu.

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