I am writing to register a formal complaint regarding the rigid turn-ordering schema enforced by the Gemini API during tool calling. The restriction that triggers the error “Please ensure that function response turn comes immediately after a function call turn” is causing repeated failures in real-world development environments, specifically when running agent-based IDE assistants like Posit Assistant. Every time local code execution or file inspection runs, this hyper-strict validation aborts the request and corrupts the entire conversation history, creating a massive productivity drag.
While other major providers like OpenAI and Anthropic handle tool-calling history flexibly without crashing over turn adjacency or diagnostic traces, Gemini’s API treats minor message sequencing variations as fatal schema violations. This design decision makes Gemini effectively unusable in multi-turn agent loops that interact with local tools.
In fact, when troubleshooting this exact failure, Gemini itself advised that the most immediate and reliable fix was simply to abandon the Gemini provider and switch to Claude or GPT-4o, because those APIs do not break under standard agent workflows. If Google insists on maintaining this fragile API contract rather than bringing its turn validation in line with industry standards, I will follow that advice and move all of my production and interactive workflows to your competitors permanently.