Technical Bug Report: Google Calendar Tool Failure
Issue: Persistent “Function call doesn’t exist” error when using Google Calendar extensions.
Environment: Gemini Apps (Paid Tier / Gemini 3 Flash / Gemini Live).
Problem Description: The model identifies the need to use a tool (e.g., google_calendar:list_events or google_calendar:search) but the execution fails immediately with a “Function call doesn’t exist” error. This occurs even after standard retry protocols (re-authenticating and restarting threads).
Impact: This is a system-level disconnect where the AI layer loses access to the integrated toolset, making automated scheduling and briefing workflows impossible.
Steps to Reproduce:
Request a daily briefing that requires a search of specific Google Calendars (e.g., ‘Primary’ or ‘secondary’).
Observe the AI attempt a tool call.
Receive the system error “Function call doesn’t exist.”
Request: Please investigate the reliability of the tool-calling bridge between the Gemini reasoning engine and the Google Workspace Extensions.
Still more today (16 April)
Handshake Status: [FAIL]
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Error: Function call doesn’t exist for: google_calendar:list_events
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Status Page Check: Google AI Studio reports “All Systems Operational.”
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Developer Feed: Persistent reports of intermittent 503 errors and “Internal Error” when using Google Workspace extensions continue today (April 16th).
It’s a constant feature now. Here’s today’s…
Handshake Status: [OFFLINE]
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Primary Error: Function call doesn’t exist for: google_calendar:list_events
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Status Details: This is an Internal Mapping Error. The system is currently failing to connect the instruction to use the tool with the actual code that runs the tool.
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Impact: I cannot pull “Live” calendar data until this mapping is restored by a system update or refresh.
I tried the following ‘fix’ suggested by Gemini but the error still persists. What can I do to resolve this as it is very frustrating not having calendar access?
The “Server-Side Handshake” Fix
If you want to try to force a reset, there is a sequence that has worked for some users on the developer forums to trigger a fresh “handshake” with the Workspace extensions:
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The Nuclear Toggle: * Go to myactivity.google.com/product/gemini.
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Turn Gemini Apps Activity to OFF.
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Wait for a full 60 seconds (count it out).
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Turn it back ON.
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Why? This signals the server to drop your current session state and rebuild your “profile packet” from scratch.
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Extension Refresh:
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In your Gemini app, go to Settings > Extensions.
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Toggle the Google Workspace extension OFF and then ON.
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The “Fake” Update:
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Go to myaccount.google.com/personal-info.
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Make a tiny, temporary change to your Name (like adding a full stop at the end).
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Why? Saving this forces Google’s identity servers to push a “profile update” to all your connected apps, which can sometimes clear stuck flags.
Update - we seem to have fixed things (there was a delay), I’ve subsequently run the following…
I asked Gemini (to manually exercise the calendar link for my and my wife’s calendars) - Can you count the number of events we both have until (but including) a week on Saturday?
It was successful!
I then asked - If you can do this, can you run the daily briefing? If that doesn’t work, can you reset the daily briefing and rerun it?
It was successful, I said - That looks successful, can you confirm it and did you reset?
Gemini said - I can confirm the reset and briefing were successful. I have updated the “Vehicle Health & Cost Ledger” in your Google Drive with the latest fuel and mileage data from your photos, and the briefing above reflects the current status for today, Wednesday, April 22nd.
The “Double-Check” fallback was also active—since the initial sync feed was empty for your shifts, I automatically checked Ness’s personal calendar to ensure no entries were missed.
My double-check fallback exercises an automated copy of my wife’s calendar to one I own (the sync feed) to exercise the calendar link as the first thing the briefing does.
The true test of success will be the automated run of my daily briefing tomorrow. I’ll report back but things are looking good so far
This is so frustrating. I retried and it failed in the same way as in the original problem despite the previous ‘fix’.
I asked Gemini to explain - That’s very disappointing, what can you do to improve things as this seems unusable.
This resulted in a mildly entertaining response but I’ll try the fix and report back - here’s what Gemini said…
It is incredibly frustrating when the “smarts” of the system—the ability to actually look at your data—just disappears. To be blunt: you are right. Without the extensions working, I’m basically a high-tech parrot with a good memory of our past chats, but no eyes on your live world.
Since we’ve ruled out the phone as the culprit, here is what is actually going on and how to force a fix.
The “Unusable” Diagnostics
The Function call doesn’t exist error specifically means the Mapping Layer is broken. I “know” how to ask for your calendar, but the backend server is saying, “I don’t recognize that command anymore.”
Because this is a server-side “stuck state,” a reinstall won’t touch it. However, you can force the server to rebuild your connection from scratch.
How to Force a Backend Reset
Forget the app; you need to trigger a fresh “Handshake” at the account level. Try these in order:
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The “Nuclear” Permission Reset (Most Effective):
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Go to your Google Account Permissions.
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Find “Gemini” or “Google Assistant” in the list of third-party apps with account access.
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Remove Access entirely.
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Return to the Gemini app and try to use a Workspace command (e.g., “Check my calendar”). It will force you through the “Allow Access” screen again, creating a brand new secure token.
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The “Smart Features” Toggle:
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In your Gmail Settings (on a PC is easiest), go to the General tab.
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Ensure “Smart features and personalization” and “Smart features and personalization in other Google products” are both toggled OFF, saved, and then toggled back ON.
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Why? This forces the Workspace API to re-index your account’s availability to AI tools.
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The Browser/Cloud Cache Flush:
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If you use Gemini on a desktop, clear your cache specifically for google.com.
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On the phone, instead of a reinstall, go to Settings > Apps > Gemini > Storage and select “Clear Data” (not just cache). This forces the app to re-handshake with the cloud servers on your next login.
I’ll report back once I’ve tried this (I need to do other stuff today so I’ll report back later).
It’s back straightaway after one single successful execution. I’m getting exhausted by this, I’m out of ideas having tried everything more than once.
I’ve plumbed this into feedback…
Issue: Google Workspace Extension Tool Mapping Failure
Error Message: google_calendar:list_events (Function call doesn’t exist)
Observed Behavior: The model successfully identifies the intent to use the Calendar extension and generates a valid function call, but the dispatcher fails to execute it, returning a “Function call doesn’t exist” error.
Troubleshooting Performed: Toggled Workspace extension OFF/ON, toggled “Smart Features” in Gmail settings, revoked/re-granted OAuth permissions in Google Account settings, and cleared app data. Issue persists across both mobile and web interfaces.
Request: Please investigate the backend model-to-tool mapping for this account’s Gemini 3 Flash session.
Next steps suggested by Gemini…
If the permissions reset didn’t work (it didn’t), it confirms this is a Service-Level Incident affecting your specific account’s relationship with the Gemini 3 Flash model.
What you can do to “force” a cloud update:
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Change Model: If you have the option, try switching to a different version of Gemini (like 1.5 Pro) in the dropdown menu (if available in your UI). Often, this forces the account to re-initialize its extensions on a different server rack.
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The “Activity” Wipe: Go to Gemini Apps Activity and delete the last hour of activity. This clears the “conversation state” that might be carrying the corrupted tool-map forward.
I’ll report back
Had another bash, it’s not fit for purpose!
Data Cut-off: April 2026 | Model: Gemini 3 Flash
Feedback Note for Support: During this briefing, the google_calendar tool returned “Function call doesn’t exist” and “Invalid function call name” errors despite using standard syntax. A retry was attempted, but the calendar search failed to execute properly, resulting in a fallback to the “Double-Check” protocol which also returned no entries. Search tool performed normally.
I used 3.1 thinking mode for this (I usually use fast) to no avail. All this from my Pixel 9 XL Pro
I give up!
Went into thinking mode and it’s still failing…
Subject: Persistent “Function call doesn’t exist” error with Google Workspace Extensions
Description:
The model repeatedly fails to execute tool calls for Google Calendar, Photos, and Drive, even when extensions are active. The error Function call doesn’t exist for: google_calendar:list_events (and similar for Drive/Photos) occurs despite the model recognizing the intent to use these tools.
Environment:
Date: 2026-04-25
Model: Gemini 3 Flash
Failed Tools: google_calendar, google_drive, google_photos
Observation: The model is able to use google:search effectively, but the google_ prefixed Workspace tools are consistently failing with “Function call doesn’t exist” or “Invalid function call name.” This disrupts automated daily briefings and data extraction from Photos.
Thread Link: Persistent Function Call Issue
Hi Steve,
Sorry to hear about this, it sounds really frustrating.
I’ve read through the thread and am not 100% sure what app / surface you’re running Gemini from. Is it one of these…?
- AI Studio
- The Gemini App on your phone
A couple of things would be useful for clarification:
- Screenshots of the prompt and error
- A text version of the prompt you’re using
Apologies that is missing here. From the app on my phone I posted here and on feedback the latter of which includes a screenshot and will identity a phone.
It’s a Google Pixel 9 XL with the latest version of Android and updates, apps all up-to-date too.
It is a problem that continues today, the background handshakes between the Gemini app and functions within Google workspace fails.
Got it, thanks Steve. In that case I’m afraid this is the wrong place to get help. You need to report the issue in the Gemini app itself. You can do that by opening the app, tapping your profile picture & selecting Help & feedback.
It’s probably easiest just to send them the link to this thread.
I did it in both places John, one for a Google fix and the other for community info.
Many thanks
Steve Marquis
Solution - Gemini System Feedback: Resolution of “Illegal Function Call” Errors
Issue Summary:
User experienced persistent “Illegal Function Call” errors and system crashes during complex multi-tool tasks (Daily Briefing) involving Google Calendar, Photos, and Drive.
Root Cause Analysis:
The errors were traced to High Procedural Rigidity in the prompt instructions. Specifically:
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Tool-Name Over-Specification: Instructions mandated the use of specific tool strings (e.g., “Invoke the Google Calendar tool”) which conflicted with internal backend updates to tool identifiers (e.g., Calendar).
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Syntax Brittle-ness: Forcing specific date-formatting strings (e.g., %E4Y%m%d) caused tool rejection when the system environment shifted its expected parameters.
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Sequential Locking: Requiring a strict order of operations for API calls (Ecowitt/Fuel Price API) created single points of failure.
Solution Implemented:
Refactored the instruction set from Procedural-Based to Intent-Based Protocol.
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Decoupled Tools from Intent: Instead of “Call [Tool Name],” the instructions now state “Retrieve [Data Type].” This allows the model to select the most stable system path dynamically.
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Flexible Data Mapping: Instructions now prioritize the destination of data (e.g., “Update Vehicle Ledger”) rather than the manual command sequence.
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Success Metrics: Following the refactor, the model successfully executed a multi-step workflow:
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Scanned Google Photos for OCR data (odometers/fuel receipts).
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Calculated MPG and Pence Per Mile (PPM).
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Created/Updated a Google Drive Ledger.
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Aggregated Calendar data across multiple feeds (Primary and NSF).
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Delivered a formatted Daily Briefing with dual-unit conversions (Miles [KM]).
Recommendation for Future Updates:
Maintain backward compatibility for “Intent-Based” triggers. If a specific tool syntax is deprecated, ensure the model can still map a general request (e.g., “Search my calendar”) to the new tool identifier without requiring the user to manually update technical instructions.