compat with opencode and handle tool errors better

[dylan-deepshard]

add to opencode like:

$ cat ~/.config/opencode/config.json                                                                                                     
{
  "$schema": "https://opencode.ai/config.json",
  "provider": {
    "myprovider": {
      "npm": "@ai-sdk/openai-compatible",
      "name": "IF2",
      "options": {
        "baseURL": "http://localhost:8080/v1",
        "apiKey": "sk-truffle-is-free"
      },
      "models": {
        "GLM-4.7-Flash" : {
          "name": "GLM-4.7-Flash",
          "limit": {
            "context": 60000,
            "output": 65536
          }
        }
      }
    }
  }
}
```