[BUG] Can't get headless claude to run in pipeline when connecting to Azure Foundry models

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?

I've tried many variations from the linked issue, and while I can get Foundry to work in local context with environment variables, when running remote in pipeline I can't figure out why it isn't working.

Claude Code CLI v2.0.58/2.0.59 hangs indefinitely (60s timeout) when running in Azure DevOps hosted agents with Microsoft Foundry integration. The CLI produces zero output before hanging - not even debug messages.

What Should Happen?

I've tried running a single command with no extra prompt setup to just confirm it is working, and claude --debug --print --dangerously-skip-permissions --output-format text respond with a haiku from my output doesn't work.

The templated command that is generated from is:

      # Connectivity check: validate Claude API access before main execution
      echo "##[section]Testing Claude API connectivity"
      CONNECTIVITY_CMD=("${CLAUDE_CMD}" --debug --print --dangerously-skip-permissions --output-format text "respond with a haiku")
      echo "##[command]${CONNECTIVITY_CMD[*]}"

      set +e
      timeout 60 "${CONNECTIVITY_CMD[@]}" >/dev/null 2>&1
      CONNECTIVITY_EXIT_CODE=$?
      set -e

      if [ ${CONNECTIVITY_EXIT_CODE} -ne 0 ]; then
        if [ ${CONNECTIVITY_EXIT_CODE} -eq 124 ]; then
          echo "##vso[task.logissue type=error]Claude API connectivity check timed out after 60 seconds"
        else
          echo "##vso[task.logissue type=error]Claude API connectivity check failed with exit code ${CONNECTIVITY_EXIT_CODE}. Unable to reach model."
        fi
        exit 1
      fi
      echo "##[info]Claude API connectivity verified successfully"

Error Messages/Logs

##[error]Claude API connectivity check timed out after 60 seconds


I can't get it to respond.
Based on the issue feedback earlier, I tried with debug flag, environment variable and more but it won't show me any output at all to know what's wrong. 

I've added logging to confirm the variables are set:


Azure AI Foundry Configuration (Required)
##[info]┌──────────────────────────────────────────────────────────────┐
##[info]│ CLAUDE_CODE_USE_FOUNDRY      = 1                             │
##[info]│ ANTHROPIC_FOUNDRY_RESOURCE   = sheld-[REDACTED]-eastus2
##[info]│ ANTHROPIC_FOUNDRY_API_KEY    = [REDACTED]                    │
##[info]└──────────────────────────────────────────────────────────────┘
Model Configuration
##[info]┌──────────────────────────────────────────────────────────────┐
##[info]│ ANTHROPIC_DEFAULT_HAIKU_MODEL  = claude-haiku-4-5
##[info]│ ANTHROPIC_DEFAULT_SONNET_MODEL = claude-sonnet-4-5
##[info]│ ANTHROPIC_DEFAULT_OPUS_MODEL   = claude-opus-4-5
##[info]└──────────────────────────────────────────────────────────────┘
Debug Configuration
##[info]CLAUDE_LOG_LEVEL=debug
##[info]CLAUDE_DEBUG=true
##[info]CLAUDE_HOME will use default: $HOME/.claude
##[info]Skills directory found with 0 files
##[info]ANTHROPIC_MCP_CONFIG set to: /home/vsts/work/_temp/.cache/mcp-config.json

Steps to Reproduce

I've tried to configure my agent directory so it had skills and other settings.

I have a template repo that gets cloned containing all the special claude prompts and skills.

      TARGET_CLAUDE_DIR="${HOME}/.claude"
      rsync -av "${SOURCE_CLAUDE_DIR}/" "${TARGET_CLAUDE_DIR}/"

So before claude code is called, I have copied all the config settings over and confirmed with this output it shows:

rsync -av "/home/vsts/work/1/autopilot/.claude/" "/home/vsts/.claude/"
sending incremental file list
./
CLAUDE.md
settings.json
agents/
agents/azure-devops-manager.md
commands/
commands/devex-docs-review.md
commands/devex-pr-review.md
skills/
skills/azure-repos-threads/
skills/azure-repos-threads/SKILL.md
skills/azure-repos-threads/scripts/
skills/azure-repos-threads/scripts/Check-CodexAzdoEnvironment.ps1
skills/azure-repos-threads/scripts/Get-CodexAzdoMainProgressThread.ps1
skills/azure-repos-threads/scripts/New-CodexAzdoThreadComment.ps1
skills/azure-repos-threads/scripts/New-CodexAzdoThreadSuggestion.ps1
skills/azure-repos-threads/scripts/Update-CodexAzdoMainProgressThread.ps1
skills/git-diff-analyzer/
skills/git-diff-analyzer/SKILL.md

sent 94,454 bytes  received 287 bytes  189,482.00 bytes/sec
total size is 93,179  speedup is 0.98
##[info]Successfully synced .claude configuration to /home/vsts/.claude
##[info]Contents of /home/vsts/.claude: /home/vsts/.claude
├── CLAUDE.md
├── agents
│   └── azure-devops-manager.md
├── commands
│   ├── devex-docs-review.md
│   └── devex-pr-review.md
├── settings.json
└── skills
    ├── azure-repos-threads
    │   ├── SKILL.md
    │   └── scripts
    │       ├── Check-CodexAzdoEnvironment.ps1
    │       ├── Get-CodexAzdoMainProgressThread.ps1
    │       ├── New-CodexAzdoThreadComment.ps1
    │       ├── New-CodexAzdoThreadSuggestion.ps1
    │       └── Update-CodexAzdoMainProgressThread.ps1
    └── git-diff-analyzer
        └── SKILL.md

7 directories, 12 files

I've run commands to

# CLI responds immediately
$ claude --version
# Output: 2.0.59 (Claude Code)

# Network connectivity confirmed
$ curl -sS --max-time 10 -o /dev/null -w "HTTP %{http_code}\n" "https://<resource>.services.ai.azure.com"
# Output: HTTP 200

Environment Variables Set

CLAUDE_CODE_USE_FOUNDRY=1
ANTHROPIC_FOUNDRY_BASE_URL=https://<resource>.services.ai.azure.com
ANTHROPIC_FOUNDRY_API_KEY=<redacted>
ANTHROPIC_DEFAULT_HAIKU_MODEL=claude-haiku-4-5
ANTHROPIC_DEFAULT_SONNET_MODEL=claude-sonnet-4-5
ANTHROPIC_DEFAULT_OPUS_MODEL=claude-opus-4-5
CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=1
DO_NOT_TRACK=1

Iterations Tested

Iteration 1: Basic invocation

• Command: claude --debug --print --dangerously-skip-permissions --output-format text "respond with a haiku"
• Result: Hangs 60s, no output

Iteration 2: Added pre-flight diagnostics

• Added claude --version check (works)
• Added curl connectivity test (works - HTTP 200 in ~80ms)
• Result: Still hangs on actual command

Iteration 3: Isolated CLAUDE_HOME

• Used env CLAUDE_HOME=/tmp/.claude-test claude ...
• Hypothesis: MCP config with invalid paths causing hang
• Result: Still hangs

Iteration 4: Removed CLAUDE_CODE_SKIP_FOUNDRY_AUTH

• Removed undocumented CLAUDE_CODE_SKIP_FOUNDRY_AUTH=1 variable
• Result: Still hangs

Iteration 5: Isolated HOME (pending)

• Using HOME=/tmp/.claude-test-home instead of CLAUDE_HOME
• Simplified command without arrays/subshells
• Result: No difference, still hangs.

Key Observations

1. Zero output: The CLI produces absolutely no output - no debug logs, no errors, nothing. It just hangs silently.

1. Version works: claude --version responds instantly, proving the CLI binary executes.

1. Network works: Direct HTTPS to Foundry endpoint returns HTTP 200 in <100ms.

1. Local works: The same configuration works locally on macOS.

1. Memory stable: Agent memory stays around 1GB during hang - no memory leak.

1. CPU idle: CPU usage drops to <1% during hang - CLI is waiting on something, not spinning.

Local Testing

export CLAUDE_CODE_USE_FOUNDRY=1
# NOPE: export ANTHROPIC_FOUNDRY_BASE_URL='https://<resource-name>.services.ai.azure.com' // API Error: 404 {"error":{"code":"404","message":"Resource not found"}}
export ANTHROPIC_FOUNDRY_BASE_URL='https://<resource-name>.services.ai.azure.com/anthropic'
export ANTHROPIC_FOUNDRY_API_KEY="$(az cognitiveservices account keys list --name '<resourcename>' --resource-group '<rg>' --subscription '<subscription>' --query key1 -o tsv)"
export ANTHROPIC_DEFAULT_HAIKU_MODEL=claude-haiku-4-5
export ANTHROPIC_DEFAULT_SONNET_MODEL=claude-sonnet-4-5
export ANTHROPIC_DEFAULT_OPUS_MODEL=claude-opus-4-5
export CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=1
export DO_NOT_TRACK=1
claude --debug --print --dangerously-skip-permissions --output-format text "respond with a haiku"

So one note in running this in my local test is that /anthropic is not documented as required, but with base url it made an immediate difference.

When using ANTHROPIC_FOUNDRY_RESOURCE=<resource> locally in my terminal it also worked, but not with base url missing the /anthropic path.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.0.59

Platform

Other

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Non-interactive/CI environment

Additional Information

Environment

• Claude Code Version: 2.0.58, 2.0.59 (latest)
• Platform: Azure DevOps Hosted Agents (Ubuntu, ubuntu-latest)
• Foundry Endpoint: https://<resource>.services.ai.azure.com, and also have used ANTHROPIC_FOUNDRY_BASE_URL as well as basic resource <resource>
• Authentication: API Key (ANTHROPIC_FOUNDRY_API_KEY)
• Node.js: v22.x