Remote trigger mcp_connections not loaded as tools in scheduled agent sessions

Bug Description

MCP connections attached to remote triggers (scheduled agents) are not being loaded as available tools in the remote session. The agent cannot discover or use any MCP tools, even though mcp_connections are correctly configured on the trigger.

Environment

• Claude Code CLI (macOS)
• Remote triggers via claude.ai/code/scheduled
• Model: claude-sonnet-4-6

Steps to Reproduce

1. Create a remote trigger with mcp_connections attached (e.g., Gmail and Slack connectors from claude.ai):

``json
"mcp_connections": [
{"connector_uuid": "...", "name": "Gmail", "url": "https://gmail.mcp.claude.com/mcp"},
{"connector_uuid": "...", "name": "Slack", "url": "https://mcp.slack.com/mcp"}
]
``

1. The trigger prompt instructs the agent to use ToolSearch to discover MCP tool names
2. Run the trigger via RemoteTrigger API with action: "run" or wait for scheduled execution

Expected Behavior

The remote agent session should have MCP tools available (e.g., mcp__Gmail__gmail_search_messages, mcp__Slack__slack_send_message, etc.) matching the mcp_connections configured on the trigger.

Actual Behavior

• ToolSearch returns no MCP tools — only built-in tools (Bash, Read, Write, etc.)
• The agent reports: "Gmail MCP tools not found" / "Slack MCP tools not found"
• Fallback to curl for Slack webhook also fails with exit code 56 (connection reset), suggesting network restrictions in the remote environment

Additional Context

• The same MCP connectors work perfectly in local Claude Code sessions (verified by calling mcp__claude_ai_Gmail__gmail_get_profile and mcp__claude_ai_Slack__slack_read_user_profile locally)
• The connectors are authenticated and valid (confirmed via local testing)
• The allowed_tools field was also updated to remove restrictive whitelisting (the API expanded it to the full default set), but this did not resolve the issue
• This previously worked — the triggers were created on 2026-03-27 and were functional initially, then stopped working sometime after
• Outbound network access (curl to hooks.slack.com) is also blocked in the remote environment, preventing webhook fallback

Questions

1. Is this a known issue with mcp_connections on remote triggers?
2. Are others experiencing the same problem?
3. Is outbound network access intentionally restricted in remote agent sessions?

Workaround

Running the same prompts locally via Claude Code CLI works perfectly since local MCP connections are available.