Anthropic API / Claude Code / Anthropic API

Anthropic API 500 Server Error — Non-Fatal Lock Acquisition Failure

User encounters Anthropic API 500 internal server error when using Claude Code desktop app; needs to understand if this is transient or requires action. Includes evidence for Anthropic API / Claude Code troubleshooting demand.

Source-backed Last updated May 23, 2026 1 source Needs local verification

Category: Anthropic API
Error signature: API Error: 500 status code (no body). NON-FATAL: Lock acquisition failed for /Users/.../.local/share/claude/versions/
Quick fix: Compare the failing environment with a known working setup, then change one configuration value at a time.
Updated: May 23, 2026
Verification status: Source-backed
Evidence: 1 public source URL

Before you change production

This page includes public source URLs in the imported troubleshooting record. Compare those references with your version and environment before applying changes.

Reproduce the smallest failing action and save non-secret logs before changing configuration.
Check versions for Anthropic API / Claude Code, related SDKs, package managers, CI runners, and hosting providers.
Change one setting or dependency at a time, then rerun the same failing command or request.
Avoid destructive commands, credential rotation, billing changes, or security relaxations without a rollback plan.

What this error means

API Error: 500 status code (no body). NON-FATAL: Lock acquisition failed for /Users/.../.local/share/claude/versions/ is a Anthropic API / Claude Code failure pattern reported for developers trying to user encounters anthropic api 500 internal server error when using claude code desktop app; needs to understand if this is transient or requires action.. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

Fresh issue from anthropics/claude-code #61827 filed today (2026-05-23) with complete environment info, stack trace, and feedback ID. Labels include 'area:api' and 'api:anthropic'. High commercial value as paid API service returning 500 errors to paying users. Category maps directly to Anthropic API.

Common causes

Fresh issue from anthropics/claude-code #61827 filed today (2026-05-23) with complete environment info, stack trace, and feedback ID. Labels include 'area:api' and 'api:anthropic'. High commercial value as paid API service returning 500 errors to paying users. Category maps directly to Anthropic API.

Quick fixes

Confirm the exact error signature matches API Error: 500 status code (no body). NON-FATAL: Lock acquisition failed for /Users/.../.local/share/claude/versions/.
Check the Anthropic API / Claude Code account, local tool state, and provider configuration involved in the failing workflow.
Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

Verify the command, editor, extension, or API client that produced the error.
Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

Capture the exact error message and the command, editor action, or request that triggered it.
Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
Review the source evidence below and compare it with your environment.
Apply one change at a time and rerun the smallest failing action.
Keep the working fix documented for the team or deployment environment.

How to prevent it

Keep provider/tool configuration documented.
Record non-secret diagnostics such as tool version, provider name, model name, and command path.
Add a lightweight check before CI or production workflows depend on the tool.

Diagnostic flow for this page

Match API Error: 500 status code (no body). NON-FATAL: Lock acquisition failed for /Users/.../.local/share/claude/versions/ exactly before applying the quick fix.
Compare the failing environment with Anthropic API / Claude Code versions, account scope, provider settings, and deployment context.
Check the listed common causes in order, starting with the cause that best matches your logs.
Use the evidence status below to decide whether to confirm against public sources or official documentation.
Apply one reversible change, rerun the smallest failing action, and keep rollback notes.

FAQ

What does API Error: 500 status code (no body). NON-FATAL: Lock acquisition failed for /Users/.../.local/share/claude/versions/ mean in Anthropic API / Claude Code?

API Error: 500 status code (no body). NON-FATAL: Lock acquisition failed for /Users/.../.local/share/claude/versions/ indicates the workflow described by "Anthropic API 500 Server Error — Non-Fatal Lock Acquisition Failure" failed in a Anthropic API context. Start by confirming the exact signature and the component that emitted it.

What should I check first for API Error: 500 status code (no body). NON-FATAL: Lock acquisition failed for /Users/.../.local/share/claude/versions/?

Check whether this cause matches your environment: Fresh issue from anthropics/claude-code #61827 filed today (2026-05-23) with complete environment info, stack trace, and feedback ID. Labels include 'area:api' and 'api:anthropic'. High commercial value as paid API service returning 500 errors to paying users. Category maps directly to Anthropic API.

Is the API Error: 500 status code (no body). NON-FATAL: Lock acquisition failed for /Users/.../.local/share/claude/versions/ guidance source-backed?

The "Anthropic API 500 Server Error — Non-Fatal Lock Acquisition Failure" page is labeled source-backed. It has 1 public source URL from github.com, so use that evidence status when deciding how much additional verification you need.

When should I avoid the quick fix for API Error: 500 status code (no body). NON-FATAL: Lock acquisition failed for /Users/.../.local/share/claude/versions/?

For "Anthropic API 500 Server Error — Non-Fatal Lock Acquisition Failure", avoid applying "Compare the failing environment with a known working setup, then change one configuration value at a time." when the error text differs, the affected version or provider is different, or the change would touch credentials, billing, DNS, production deploy settings, or irreversible data.

What should I collect before debugging API Error: 500 status code (no body). NON-FATAL: Lock acquisition failed for /Users/.../.local/share/claude/versions/?

For "Anthropic API 500 Server Error — Non-Fatal Lock Acquisition Failure", collect the failing Anthropic API / Claude Code command or request, non-secret configuration, versions, timestamps, request IDs when available, and the smallest reproduction that still triggers the signature.