Model IDs with slashes are broken #15668

Description

I am running mistral.rs as my LLM service. If I configure it to load a model from my filesystem, then the model ID becomes the filesystem path, like /my/llms/Qwen3. (There does not appear to be a way to customize this today.)

So this works:

curl http://server.lan/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{ "model": "/my/llms/Qwen3", "messages": [...] }'

So I try to configure OpenCode as follows:

  "provider": {
    "philiplocal": {
      "npm": "@ai-sdk/openai-compatible",
      "name": "Philip's workstation",
      "options": {
        "baseURL": "http://server.lan/v1"
      },
      "models": {
        "/my/llms/Qwen3": {
          "name": "local Qwen3"
        }
      }
    }
  },
  "model": "philiplocal//my/llms/Qwen3",

When I open OpenCode and send a chat message, I see this in the log file:

INFO  2026-03-02T07:39:05 +1ms service=llm providerID=philiplocal modelID=/my/llms/Qwen3 sessionID=ses_3528376f9ffeEJ9cVZte9u73vG small=false agent=plan mode=primary stream
INFO  2026-03-02T07:39:05 +0ms service=provider status=started providerID=philiplocal getSDK
INFO  2026-03-02T07:39:05 +0ms service=provider providerID=philiplocal pkg=@ai-sdk/openai-compatible using bundled provider
INFO  2026-03-02T07:39:05 +1ms service=provider status=completed duration=1 providerID=philiplocal getSDK
ERROR 2026-03-02T07:39:05 +0ms service=default e=ProviderModelNotFoundError rejection

Meanwhile, OpenCode UI is waiting indefinitely for a response until I quit the program. (This is probably a separate issue, that the error is not detected and surfaced to the user.)

When I instead change the OpenCode config to remove slashes from the model key, then OpenCode correctly immediately shows a server error: "Internal Server Error: Requested model 'Xyz' is not available..."

My conclusion is that OpenCode does not support model IDs with slashes.

This is a little strange because, based on the log file, it split my requested model into the correct providerID versus modelID -- so it's not entirely confused about slashes.

I will also pursue improving mistral.rs to support giving models custom names to avoid this problem, but it would be great if OpenCode allowed this usage.

Plugins

none

OpenCode version

1.2.13

Steps to reproduce

Create an OpenCode config file with a local provider and a model ID having slashes, and try to use it. (All detail is in the bug description.)

Screenshot and/or share link

No response

Operating System

NixOS unstable

Terminal

foot