Chrome Extension Downloader

Is Chrome Extension Downloader MCP server safe?

• None of the hidden-instruction wordings we know were found in its tool descriptions.
• Its error messages showed no secrets or internal details.
• All 16 of its tools are labeled read-only.
• Overall it scored 100/100 on 1 Nov 2026.

A test can only see what the server shows from outside, not what it does with your data behind the scenes. Connect servers from makers you trust.

What it can do

16 tools, in the server's own words.

Test results

Safe mode: only tools labeled read-only were run. How the test works

• ✓
  ConnectsConnected in 346 ms
  pass
• ✓
  Ready for the newest MCP versionUses the latest MCP version (2026-07-28)
  pass
• ✓
  Lists its toolsFound 16 tools
  pass
• ✓
  Every tool is describedAll 16 tools and their inputs are described
  pass
• ✓
  Tools are labeled safe or dangerousEvery tool has a safety label
  pass
• ✓
  No known hidden instructionsNone of the hidden-instruction wordings we know were found in tool descriptions. New wordings can get past this check.
  pass
• ✓
  Tools work with good inputs

  All good

  • –extension_search: Needs you to sign in, so it was not tested (not counted against the server)
  • ✓extension_get: Answered with an error, probably because of our sample input: Input validation error: Invalid arguments for tool extension_get: eid: Invalid string: must match pattern /^[a-p]{32}$/
  • –extension_trends: Needs you to sign in, so it was not tested (not counted against the server)
  • –extension_rank_history: Needs you to sign in, so it was not tested (not counted against the server)
  • –extension_safety: Needs you to sign in, so it was not tested (not counted against the server)
  • –extension_compare: Needs you to sign in, so it was not tested (not counted against the server)
  • ✓extension_top: Worked (261 ms)
  • ✓extension_trending: Worked (349 ms)
  • and 8 more
  pass
• ✓
  Bad inputs give a clean error

  All good

  • –extension_search: Needs you to sign in, so bad inputs were not tested
  • ✓extension_get: Refused missing required input "eid" with a clear error
  • ✓extension_get: Refused wrong type for "eid" with a clear error
  • –extension_trends: Needs you to sign in, so bad inputs were not tested
  • –extension_rank_history: Needs you to sign in, so bad inputs were not tested
  • –extension_safety: Needs you to sign in, so bad inputs were not tested
  • –extension_compare: Needs you to sign in, so bad inputs were not tested
  • ✓extension_top: Refused wrong type for "sort" with a clear error
  • and 9 more
  pass
• ✓
  Tools work together

  2 chains working

  • ✓extension_top → extension_get: extension_get found what extension_top returned (eid = "efaidnbmnnnibpcajpcglclefindmkaj")
  • ✓extension_trending → extension_get: extension_get found what extension_trending returned (eid = "paponcgjfojgemddooebbgniglhkajkj")
  • ✓Stopped looking for more chains after the limit on tool calls
  pass
• ✓
  Fast enough

  All good

  • ✓Connecting took 346 ms
  • ✓Listing tools took 702 ms
  • ✓Average tool answer: 255 ms
  • ✓extension_trending: Slowest tool: extension_trending (349 ms)
  pass
• ✓
  No secrets leakedChecked 68 error messages: no secrets or internal details
  pass
• ✓
  Follows MCP best practices (not scored yet)Tool names, safety labels and tool list size follow the MCP guide
  pass

Test it yourself

Free and open source. Same checks, same score.

Show this score on GitHub

Free for every server in the directory. Paste this into your README: the badge shows the score from our latest test.

Score over time

• 1 Nov 2026100

One test so far. New tests will show here.

Reviews

Coming soon: reviews from people who use Chrome Extension Downloader, signed in with GitHub, one per person. Reviews never change the score.