[BUG] Remote trigger manual run returns HTTP 500 Internal Server Error

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Manually running a remote trigger via POST /v1/code/triggers/{trigger_id}/run consistently returns HTTP 500. Triggers are created successfully and show
correct configuration, but no remote agent session is spawned. No Slack messages or Asana updates are ever delivered.

What Should Happen?

run should spawn a remote agent session that executes the prompt with access to the attached MCP connections.

Error Messages/Logs

{
    "error": {
      "message": "An internal server error occurred",
      "type": "api_error"
    },
    "request_id": "req_011CZnp7gRh3t3df2rtYirKK",
    "type": "error"

Steps to Reproduce

1. Create a remote trigger with MCP connections (Slack and/or Asana)
2. Trigger creation succeeds (HTTP 200)
3. Manually run the trigger via the run action
4. Returns HTTP 500 Internal Server Error

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.92

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Trigger Configuration

• Environment: Default (env_01Vb9bve11SWPwDqYXgtphVq, anthropic_cloud)
• Model: claude-sonnet-4-6
• MCP Connections: Slack (mcp.slack.com) and Asana (mcp.asana.com)
• Allowed tools: Bash, Read, Write, Edit, Glob, Grep
• All MCP connector permissions enabled in claude.ai/settings/connectors

Affected Trigger IDs

• trig_01ALiH7eM5FN1LZCPFveYWfi (Morning Briefing)
• trig_019RqzjRSFrnR7XpsLAzzdon (Hourly Progress Check)
• trig_014iJarwE1pScAk8SVRubKBv (Evening Summary)
• trig_01EFoGvVHFr7Faz1X7GeWJkE (Minimal Slack-only test)
• trig_013R3EoRmvtexfdAxkCMGMs2 (Debug test — returned explicit 500)

Additional Context

• Tested with both complex prompts (Asana + Slack) and minimal prompts (Slack DM only) — same result
• Trigger creation and listing work fine
• MCP tools (Slack, Asana) work correctly in local Claude Code sessions
• Platform: Windows 11 Pro, Claude Code CLI
• Earlier manual runs returned HTTP 200 but no agent activity occurred; final debug test exposed the 500