Doesn't work - Anthropic API breaking change

[jmakov]

[kaanekin05]

I have the same problem. I'm not sure if I installed correctly so this is how I set it up. My Claude CLI works fine.

Cloned the repo to /Users/kaan/opencode-claude-code-plugin

Ran

bun install
bun run build

Changed the opencode.json file at .config/opencode/opencode.json to the following, Changed the npm line to the local folder

{
  "$schema": "https://opencode.ai/config.json",
  "plugin": [
    "oh-my-openagent@latest"
  ],
  "provider": {
    "claude-code": {
      "npm": "file:///Users/kaan/opencode-claude-code-plugin",
      "models": {
        "haiku": {
          "name": "Claude Code Haiku",
          "attachment": false,
          "limit": {
            "context": 200000,
            "output": 8192
          },
          "capabilities": {
            "reasoning": false,
            "toolcall": true
          }
        },
        "sonnet": {
          "name": "Claude Code Sonnet",
          "attachment": false,
          "limit": {
            "context": 1000000,
            "output": 16384
          },
          "capabilities": {
            "reasoning": true,
            "toolcall": true
          }
        },
        "opus": {
          "name": "Claude Code Opus",
          "attachment": false,
          "limit": {
            "context": 1000000,
            "output": 16384
          },
          "capabilities": {
            "reasoning": true,
            "toolcall": true
          }
        }
      },
      "options": {
        "cliPath": "claude"
      }
    }
  }
}

I can see and select Claude Code Opus. I said Hi. It replied back and gave the error

Hi! How can I help you with your project today?

API Error: 400 {"type":"error","error":{"type":"invalid_request_error","message":"messages.2.content.0.text: cache_control cannot be set for empty text blocks"}

[unixfox]

Something has changed on anthropic API side. I need to understand what's going on. Downgrading claude code won't fix the issue.
Related: anthropics/claude-code#41729

[Ozy-Viking]

I'm getting the same issue, I will see if I can make any headway

[khalilgharbaoui]

This is addressed in PR #16 across several commits:

1. AI SDK v3 compatibility (b0f81b2): the provider now implements LanguageModelV3 correctly, fixing the usage/token tracking crash that breaks responses.

2. Empty content blocks (2fe6036, 213acbf): upstream tried to fix this in 2d6f094 then reverted in 644cad6. PR feat: selective tool proxying, session isolation, MCP bridging, and streaming fixes #16 fixes it properly — whitespace-only content blocks are filtered with .trim() checks, and the zero-block fallback uses "(empty)" instead of "(continue)" (which the model misinterprets as an instruction to resume).

3. Blank responses on error (f27ca52): if Claude CLI returns only a result message with error text (rate limit, auth failure, API error), it's now emitted as visible text instead of a blank turn.

4. Object-shaped tools (47af6af): opencode sometimes passes tools as an object map rather than an array; the scope classifier now handles both, preventing silent misclassification that could cause blank responses.

5. MCP config validation errors (dd82b11): auto-bridged MCP configs now emit correct transport types (stdio/http), preventing Claude CLI from rejecting the config and silently failing.

Together these eliminate the class of "doesn't work / blank response" issues.

[unixfox]

This repository is archived. Unfortunately I don't have enough free time to maintain it. You can find forks like:

• https://github.com/khalilgharbaoui/opencode-claude-code-plugin
• https://github.com/Aptul9/opencode-claude-code-plugin