MCP OAuth: Claude Code re-runs DCR on every authenticate, orphaning previously issued client_id
Fix MCP OAuth re-authentication loop caused by DCR being called repeatedly instead of reusing persisted credentials Includes evidence for Claude Code troubleshooting demand.
Source-backedLast updated May 20, 20261 sourceNeeds local verification
MCP OAuth: Claude Code re-runs Dynamic Client Registration (POST /oauth/register) on every authenticate, orphaning previously issued client_id and refresh_token; causes forced re-auth loop with self-hosted OAuth servers
Quick fix
Verify the account session, API key, provider settings, and environment where the failing tool is running.
Updated
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 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
MCP OAuth: Claude Code re-runs Dynamic Client Registration (POST /oauth/register) on every authenticate, orphaning previously issued client_id and refresh_token; causes forced re-auth loop with self-hosted OAuth servers is a Claude Code failure pattern reported for developers trying to fix mcp oauth re-authentication loop caused by dcr being called repeatedly instead of reusing persisted credentials. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.
Why this happens
GitHub Issue #59460 (anthropics/claude-code), created 2026-05-15, 2 comments. Detailed reproduction with RFC 7591 DCR + OAuth 2.1 servers. Category: Claude Code = AI Coding Tools per category mapping rules.
Common causes
GitHub Issue #59460 (anthropics/claude-code), created 2026-05-15, 2 comments. Detailed reproduction with RFC 7591 DCR + OAuth 2.1 servers. Category: Claude Code = AI Coding Tools per category mapping rules.
Quick fixes
Confirm the exact error signature matches MCP OAuth: Claude Code re-runs Dynamic Client Registration (POST /oauth/register) on every authenticate, orphaning previously issued client_id and refresh_token; causes forced re-auth loop with self-hosted OAuth servers.
Check the Claude Code account, local tool state, and provider configuration involved in the failing workflow.
Verify the account session, API key, provider settings, and environment where the failing tool is running.
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 MCP OAuth: Claude Code re-runs Dynamic Client Registration (POST /oauth/register) on every authenticate, orphaning previously issued client_id and refresh_token; causes forced re-auth loop with self-hosted OAuth servers exactly before applying the quick fix.
Compare the failing environment with 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.