macOS: copilot-mcp-oauth keychain prompt returns after "Always Allow"; many duplicate keychain items #5434

Problem

On macOS, a keychain prompt keeps appearing for the copilot-mcp-oauth service even after choosing "Always Allow":

security wants to use your confidential information stored in "copilot-mcp-oauth" in your keychain.

The prompt names security (/usr/bin/security), so the CLI reads the item through the security tool.

Observation

Keychain Access showed about 50 separate copilot-mcp-oauth items in the login keychain (kind "application password"), each with a different hashed account name. Their modified dates are spread over every day from 2026-09-30 to the current day, with several created or modified on the same day. The login keychain has no auto-lock timeout (security show-keychain-info reports no-timeout), so locking does not explain the repeated prompts.

"Always Allow" adds security to the access list of one item only. If the CLI creates a new item (or deletes and re-creates it) whenever a token is stored or refreshed, the new item has no grant, and the prompt returns. Old items are also never removed.

Expected

• Update an existing item in place, so a previous "Always Allow" persists.
• Remove items for tokens that are no longer used.
• Alternatively, store the OAuth tokens for all MCP servers in a single item, so one grant covers them.

Environment

• Copilot CLI 1.0.99-2, GitHub Copilot app
• macOS, login keychain
• Several remote MCP servers using OAuth (Atlassian, Jama, GitHub)

Related, but a different symptom: #4203