Model sometimes tries to use MCP tool to read skills

What version of Codex is running?

0.65.0

What subscription do you have?

Business

Which model were you using?

gpt-5.1

What platform is your computer?

MacOS

What issue are you seeing?

I'm testing the new experimental support for Skills added in #7412

Randomly, the model sometimes tries to use read_mcp_resource to open the skill files, rather than just reading the file from the filesystem. I don't have any MCP servers installed or configured at all, so I'm not sure why it would do this. It doesn't do it every time, just occasionally.

• I’ll quickly consult the relevant skills from your local skill library, then answer with a single concise paragraph as requested.

• Called local-files.read_mcp_resource({"server":"local-files","uri":"[REDACTED]/SKILL.md"})
  └ Error: resources/read failed: unknown MCP server 'local-files'

What steps can reproduce the bug?

Provide any prompt or task that results in the model choosing to read a skill. Bug only happens occasionally.

What is the expected behavior?

• Explored
  └ Read SKILL.md

Additional information

_No response_