Summary

Starting in codex-cli 0.116.0, the /mcp slash command output regressed compared with 0.115.0.

The MCP servers themselves can still be enabled/working, but /mcp no longer shows key diagnostic fields, which makes working MCP setups look broken.

Environment

• OS: Windows
• Last known good: 0.115.0
• First bad: 0.116.0
• Also reproducible in 0.121.0
• Same ~/.codex/config.toml
• Same MCP server setup
• Reproduced in terminal, not only VS Code

Expected behavior

/mcp should keep the diagnostic output format from 0.115.0, including:

• Status: enabled
• Resources
• Resource templates

Actual behavior starting in 0.116.0

/mcp switches to a reduced/different output format:

• Status: enabled disappears
• Resources disappears
• Resource templates disappears
• tool naming changes in some cases
• output can make working MCP servers look broken

Evidence

0.115.0

/mcp shows full diagnostic output like:

• context7
  • Status: enabled
  • Auth: Unsupported
  • Command: npx -y @upstash/context7-mcp@latest
  • Tools: query_docs, resolve_library_id
  • Resources: (none)
  • Resource templates: (none)

0.116.0+

/mcp no longer shows those fields and instead shows a reduced output format.

At the same time, MCP backends may still be functioning, so this appears to be a /mcp rendering/output regression rather than necessarily an MCP backend failure.

Impact

• users think MCP stopped working after upgrade
• /mcp becomes much less useful for diagnostics
• enabled state is no longer visually confirmable from the slash command

Request

Please restore the previous /mcp diagnostic output, or add a verbose mode that includes:

• status
• resources
• resource templates
• exact MCP state