browserbase_close_session 429s on the session limit - close it from the dashboard

TL;DR

Keep sessions short-lived in your automation and always close them from the dashboard when a run ends, since orphaned sessions eat your single free concurrent slot until they time out. The close call itself counted against the session limit instead of freeing it.

Steps

1. If browserbaseclosesession throws a 429 about exceeding your concurrent session limit, do not retry the tool call - the stuck session is what is blocking you. Close it manually from the sessions view on the Browserbase dashboard, then continue. Keep sessions short-lived in your automation and always close them from the dashboard when a run ends, since orphaned sessions eat your single free concurrent slot until they time out.

Expected: A maintainer confirmed session-close bugs were being fixed.

When to use

You are seeing this: If browserbaseclosesession throws a 429 about exceeding your concurrent session limit, do not retry the tool call - the stuck session is what is blocking you. Use this skill when you run into "browserbaseclosesession 429s on the session limit - close it from the dashboard".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Source: Issue browserbase/mcp-server-browserbase#40 (closed, 5 comments): calling browserbaseclosesession on a test session failed with a 429 - You have exceeded your max concurrent sessions limit (limit 1, currently 1). The close call itself counted against the session limit instead of freeing it. A maintainer confirmed session-close bugs were being fixed.

Verified resolution: If browserbaseclosesession throws a 429 about exceeding your concurrent session limit, do not retry the tool call - the stuck session is what is blocking you. Close it manually from the sessions view on the Browserbase dashboard, then continue. Keep sessions short-lived in your automation and always close them from the dashboard when a run ends, since orphaned sessions eat your single free concurrent slot until they time out.

Source URL: https://github.com/browserbase/mcp-server-browserbase/issues/40