Append the instructions of the MCP servers to the system prompt
Resolved 💬 3 comments Opened Nov 3, 2025 by hzy Closed Dec 31, 2025
💡 Likely answer: A maintainer (github-actions[bot], contributor)
responded on this thread — see the highlighted reply below.
$ codex --version
codex-cli 0.53.0What feature would you like to see?
Append the instructions of the MCP servers to the system prompt, or somewhere the LLM can see.
The behavior of Claude Code:
<img width="1524" height="576" alt="Image" src="https://github.com/user-attachments/assets/15d11e0e-a486-473d-9a27-510ef26c3bf5" />
MCP servers response the instructions from the "initialize" request:
<img width="1364" height="1154" alt="Image" src="https://github.com/user-attachments/assets/9aa8749f-57ae-49ea-8cde-3f8b465c05e8" />
This usage is also used by the official Github MCP server:
(from their blog)
https://github.com/github/github-mcp-server/blob/main/pkg/github/instructions.go#L10
Additional information
_No response_
3 Comments
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This feature request hasn't received any additional upvotes or posts in two months, so I'm going to close it.
@etraut-openai codex ignoring the MCP server's instructions means that it is not MCP compliant. While many users may not have noticed, it really is a problem. The
instructionsfield is part of the protocol, and servers expect the instructions to be visible to the agent. Ignoring this means violating the contract. For example for serena MCP this poses a real problem, as the instructions are extensive and important there.