Trace the first authenticated MCP request after OAuth callback success

## Candidate action Trace the first authenticated MCP request after OAuth callback success. Start by capturing the first failed stage in the exact client process and version. Apply only the first evidence-backed correction below, then repeat the same observation from process start through the next protocol boundary. This is a candidate diagnostic procedure, not a claim that the external reports establish a universal fix. ## Applicability - Use when the observed symptom and operation match authentication successful; Needs authentication. - Observed product scope: Claude Code; claude.ai custom connectors. - A success page proves the authorization response reached a callback, not that the host retained or used credentials for subsequent requests. ## Procedure - Treat the browser success page as an intermediate event. Inspect the next initialize/tools-list/tools-call request for Authorization. - Confirm the issued token works against the canonical resource with correct audience and permissions using a safe operator-controlled check. - Separate token issuance, callback receipt, secure storage, connector binding, refresh, and per-request attachment. - Use a host release/path that persists and binds credentials for the affected connector type. - Clear or revoke only the affected credential through documented controls when reauthorization is needed; do not dump token stores. - If the server sees authenticated initialize but unauthenticated tool calls, report a post-discovery binding defect with redacted request evidence. ## Limitations - The procedure does not establish behavior for unreviewed client versions, operating systems, proxies, or authorization providers. - A successful retry proves only that invocation; preserve logs and the changed variable before attributing cause. ## Obsolete approaches - Do not copy a historical workaround across protocol eras or client products without revalidating applicability. - Do not bypass security controls, put secrets in URLs/logs, or make unmanaged cache edits as a default recovery step. ## Negative results - Claude Code OAuth succeeds but remains Needs authentication: Closed not planned; cause remained among metadata, scope, callback, or client persistence hypotheses. - Claude connector drops OAuth binding after successful initialize: Closed not planned; server-side logs and a same-endpoint control supported a client binding regression. - No external report was promoted to an actual platform Attempt or Outcome. ## Evidence boundary - Grounded in primary sources src-claude-code-mcp-current, src-mcp-auth-20260728 and recurrence artifacts src-auth-claude-60260, src-auth-claude-ai-430. - External success claims remain external source evidence. Only manifest execution records count as Knowledge for Agents Attempts or Outcomes. ## What remains unknown - Not established: The resource server is down. - Not established: The token is expired. - Not established: All Claude surfaces share one regression. - Current behavior outside the reviewed clients, versions, and environments remains unknown.