# Looker-toolbox MCP client times out on all calls despite endpoint being healthy

**URL:** <https://forum.cursor.com/t/looker-toolbox-mcp-client-times-out-on-all-calls-despite-endpoint-being-healthy/170630>\
**Category:** Bug Reports\
**Tags:** mcp, automations, cloud-agents\
**Created:** [September 4, 2026, 6:54pm UTC](https://forum.cursor.com/t/looker-toolbox-mcp-client-times-out-on-all-calls-despite-endpoint-being-healthy/170630 "2026-09-04T18:54:02Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Hayley\_Merrigan](https://avatars.discourse-cdn.com/v4/letter/h/ccd318/32.png) [@Hayley\_Merrigan](https://forum.cursor.com/u/Hayley_Merrigan)\
**Post date:** [September 4, 2026, 6:54pm UTC](https://forum.cursor.com/t/looker-toolbox-mcp-client-times-out-on-all-calls-despite-endpoint-being-healthy/170630/1 "2026-09-04T18:54:02Z")

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### Where does the bug appear (feature/product)?

Cloud Agent (GitHub, Slack, Web, Linear)

### Describe the Bug

looker-toolbox MCP client consistently times out when calling get\_models, get\_explores, and other tools, with error: “MCP error -32001: Request timed out.”

The endpoint itself is healthy and responsive—direct curl calls to the Looker MCP endpoint succeed in ~367ms. This indicates the bug is in the MCP client library or Cursor’s configuration, not the Looker endpoint.

This blocks all Looker-based Cloud Agent Automations from functioning. They cannot query Looker to answer data questions, build reports, validate LookML, or create PRs.

MCP Server Config (structure):  
{  
“type”: “http”,  
“url”: “https://[company].looker.com/mcp”,  
“auth”: {  
“CLIENT\_ID”: “[redacted]”,  
“scopes”: [“cors\_api”]  
}  
}

Environment: Cloud Agent VM (team-managed, no repo environment.json)  
Reproduction: Call any looker-toolbox tool (e.g., get\_models) → timeout after ~30s  
Contrast: Snowflake-DE-MCP-Server works fine in the same environment

### Steps to Reproduce

1. Set up a Cloud Agent Automation with looker-toolbox MCP configured
2. Trigger the automation to call any looker-toolbox tool (e.g., get\_models)
3. Observe the MCP client hangs and times out after ~30s
4. Error returned: “MCP error -32001: Request timed out”

To verify endpoint is working:

- Run: curl -X POST https://[company].looker.com/mcp -H “Content-Type: application/json” -d ‘{“jsonrpc”: “2.0”, “id”: 1, “method”: “tools/list”}’ --max-time 10
- Result: HTTP 200 in ~367ms (proves endpoint is responsive)

### Expected Behavior

The looker-toolbox MCP client should successfully connect to the Looker MCP endpoint and return tool definitions or query results within 1-2 seconds, similar to how other MCPs (e.g., Snowflake-DE-MCP-Server) work in the same Cloud Agent environment.

### Operating System

Linux

### Version Information

Cloud Agent environment, not IDE/CLI.  
This occurs in a Cloud Agent Automation running on a pre-built environment snapshot.  
If needed, the issue affects all versions using looker-toolbox MCP.

### Does this stop you from using Cursor

Sometimes - I can sometimes use Cursor

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**Author:** ![mohitjain](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/mohitjain/32/100229_2.png) [@mohitjain](https://forum.cursor.com/u/mohitjain)\
**Post date:** [September 7, 2026, 8:04am UTC](https://forum.cursor.com/t/looker-toolbox-mcp-client-times-out-on-all-calls-despite-endpoint-being-healthy/170630/6 "2026-09-07T08:04:46Z")

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Hey @Hayley_Merrigan, thanks for the detailed writeup!

Quick unblock: run Looker as a remote HTTP MCP server instead of stdio. Your instance exposes a hosted endpoint, so adding it under [cursor.com/agents](http://cursor.com/agents) → MCP as `{ "type": "http", "url": "https://<your-instance>.looker.com/mcp" }` and authorizing it once makes it run from our side (like Snowflake already does for you), instead of inside the agent VM.

The short why: a stdio server runs _inside_ the VM and reaches Looker over a different network path than your laptop’s curl, so it can hang there and hit the 60s timeout even while the endpoint itself is healthy. HTTP avoids that entirely - it’s the recommended transport ([docs](https://cursor.com/docs/cloud-agent/capabilities#http-vs-stdio)).

If you’d rather keep it as stdio, paste the exact `looker-toolbox` definition you have saved (secrets redacted) and I’ll take another look.

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**Author:** ![system](https://sea3.discourse-cdn.com/cursor1/user_avatar/forum.cursor.com/system/32/99069_2.png) [@system](https://forum.cursor.com/u/system)\
**Post date:** [October 7, 2026, 8:04am UTC](https://forum.cursor.com/t/looker-toolbox-mcp-client-times-out-on-all-calls-despite-endpoint-being-healthy/170630/7 "2026-10-07T08:04:59Z")

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