HISTOR / MCP tools
Which MongoDB MCP tools disappear in read-only mode?
Enable read-only mode with --readOnly or MDB_MCP_READ_ONLY=true.
To see which tools your client actually receives, compare its tools/list responses before and after.
Compare your tool lists
Paste the JSON from each run. Use the same package version, client and connection settings for both. If the client paginates the list, combine every page into one tools array. The comparison runs in this browser.
The example is a small illustration of the comparison. The observed launches are described below.
The Markdown note includes the counts, selected tool names and a link to this checker.
This checks which names are advertised. Use a database user with the read role to enforce permissions at the database.
MongoDB security guidance
What HISTOR and RugSnare observed
In archived comparisons of versions 3.0.5 and 3.1.0, HISTOR’s bare launch exposed nine additional write tools.
RugSnare used --readOnly and a preconfigured connection. Both settings differed, so the comparison describes
those two launches. Use your client’s own lists to check a specific setup.
HISTOR comparison ·
RugSnare capture notes
For a local preview of the enabled tools, MongoDB documents --dryRun. Its output includes configuration settings.
MongoDB dry-run instructions