Reported issues for growthbook-mcp
Pod holds 9 of 9 problems reported by people outside the maintainer team. Issues filed by the project's own owners, members and collaborators are excluded entirely — a maintainer's release checklist is not a warning to a prospective user.
Back to growthbook-mcp.
Most discussed
MCP get_attributes tool fails with HTTP 400 due to unsupported limit query parameter
The get_attributes MCP tool appears to be sending a limit query parameter to the GrowthBook attributes endpoint, which results in a 400 response. This occurs even when using an Admin API key, suggesting this is not a permissions issue but an MCP/API compatibility issue.
Environment:
GrowthBook Cloud Claude Desktop + Claude Code GrowthBook MCP (@growthbook/mcp@latest) Reproduced with both Global Experimenter and Admin API keys
Steps to Reproduce:
Configure GrowthBook MCP in Claude Desktop wit
Read the thread · 2026-06-03 · open · external user · 0 comments
create_feature_flag fails with "No data source or assignment query found" when org has no data source
Version: @growthbook/mcp@1.8.1 · GrowthBook Cloud
What happens: Calling create_feature_flag for a simple boolean flag fails with:
No data source or assignment query found. Experiments require a data source/assignment query. Set these up in the GrowthBook and try again.
This happens in any org that has no data source and no experiments — e.g. a project using GrowthBook purely for feature flags. The docs state a data source is only needed for experiments, so flag creation sh
Read the thread · 2026-05-30 · open · external user · 0 comments
Creating experiment with targeted attributes supported
MCP to support configuring targeting attributes (e.g. conditions, audiences, geo rules) at the time of experiment creation, enabling fully end-to-end experiment setup via MCP. Currently, this limitation requires users to fall back to the UI or API, breaking the otherwise streamlined workflow. Expanding MCP to include targeting configuration would significantly improve automation, consistency, and adoption for enterprise use cases.
Read the thread · 2026-05-22 · open · external user · 0 comments
OAuth Support
The ability to log in using OAuth
Read the thread · 2026-03-16 · open · external user · 0 comments
Feature : Custom Field Support
We are starting to use your MCP server, but there are some key things missing for us to fully use it:
- CustomFields of an experiment cannot be set/modified via the MCP
- CustomFields of a feature flag cannot be set/modified via the MCP
Read the thread · 2026-03-09 · closed · external user · 1 comment
Feature: Create per‑environment experiment rules
I'm working on automating experiment setup using the GrowthBook MCP with AI agents (Cursor/Claude Code).
Running into a limitation I wanted to discuss.
The goal: Automatically create feature flags with experiment rules that have different targeting per environment.
In other words, I want to create and attach one experiment rule per environment.
For example, we need production rules to have a is_test_user: true targeting so test engineering can validate in dark prod, while staging/dev run wi
Read the thread · 2026-01-29 · open · external user · 0 comments
Feature flag validation doesn't allow "." but it should
GrowthBook has these requirements for feature flag names:
Only letters, numbers, and the characters _, -, ., :, and | allowed. No spaces. Cannot be changed later!
The current MCP validation logic is too strict, not allowing "."
Read the thread · 2025-10-29 · closed · outside contributor · 1 comment
Add project parameter support when creating feature flags
First of all, thank you for creating and maintaining this excellent MCP server for GrowthBook! We've been using it at our company and it's been incredibly helpful for streamlining our feature flag workflow.
🎯 Feature Request
We would love to see support for assigning a project to feature flags during creation via the create_feature_flag tool.
📋 Current Behavior
Currently, when creating a feature flag using the MCP tool, we can set:
idvalueTypedefaultValue- `fileE
Read the thread · 2025-10-28 · closed · external user · 1 comment
Most recent
Return customFields in read tools
Following on from #39 (resolved in v1.8.0), customFields can now be set
on experiments and feature flags via the MCP — but they are not returned
by get_experiments or get_feature_flags.
Please include customFields in the output of these read tools so the
full round-trip (write and read) is supported.
Read the thread · 2026-06-24 · open · external user · 0 comments
The remaining reports are on the project's issue tracker.