Auto-deny MCP elicitations for Xcode 26.4 clients#21113
Merged
Conversation
mzeng-openai
approved these changes
May 5, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to subscribe to this conversation on GitHub.
Already have an account?
Sign in.
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Summary
Xcode 26.4 was built against app-server behavior from before MCP elicitation requests became client-visible in CLI 0.120.0 via #17043. That client line does not expect the new events/messages, so this PR restores the old behavior for exactly that client/version combination.
The compatibility handling stays in the app-server layer: when the initialized client is
Xcodeand its version starts with26.4, the app server marks the live Codex thread so MCP elicitations are auto-denied. The flag is applied on thread start/resume/fork/turn attachment, carried throughCodex/CodexThread, and stored onMcpConnectionManagerso refreshed MCP managers preserve the behavior.Notes
This is intentionally narrow and includes a TODO to remove the compatibility path once Xcode 26.4 ages out.