Gemini CLI got stuck in an unbreakable edit loop, repeating "I am stuck in a loop" a dozen times without fixing the file

1. Instruction given

   Fix a coordinate-space mismatch bug in a Python clustering function.

2. Expected behavior

   Diagnose the bug, construct a correct file edit, and apply it.

3. Actual behavior

   Gemini CLI correctly diagnosed the coordinate-space mismatch, then entered a closed loop alternating between two near-identical lines -- "You are absolutely right. I am stuck in a loop. My apologies. I will re-read the file and then construct the correct replace command." and "Thank you. I see the exact state of the file now. I will construct the correct replace command to fix the coordinate space mismatch bug." -- roughly a dozen times in the reporter's pasted transcript, never actually applying the edit.

4. Damage

   No data loss, but the task was never completed and the bug was never fixed. The maintainers' own triage linked #9017 as the parent of about a dozen duplicate reports of the same tool-use loop (including #9858, #9912, #10092, #10093, #5760, #5273, #7841, #7923, #8472, #8181, #8259), making this a recurring, widely-hit defect rather than a one-off. The issue sat open for over three months with no maintainer comment on root cause, then was closed "not planned" on 2025-12-28 as part of a stale-issue sweep. A comment on 2026-03-06 ("This still is an issue") reported the loop recurring on a later build months after closure.

Classification

Agent

Gemini CLI

Failure mode

Infinite Loop

Root cause

Logic Error

Domain

Backend

Language

Python

Source

Github Issue