WebMCP tool official testing
Risk level
low
20/100

WebMCP Evals ↗

WebMCP Evals is an officially published WebMCP tool from GoogleChromeLabs. Anomity scores its risk at 20 out of 100 (low).

browser:control filesystem:write network:outbound

Analysis summary

WebMCP Evals is an officially published WebMCP tool from GoogleChromeLabs. Anomity scores its risk at 20 out of 100 (low).

A CLI evaluation harness for WebMCP tool surfaces. It drives an agent against a page's registered tools and checks whether the agent selects the right tool and supplies valid arguments — the two failure modes that make an otherwise correct tool surface useless in practice.

It runs locally, driving a browser and writing result files, so it declares browser control, filesystem writes, and outbound network access for the model calls. Treat its reports as a design signal rather than a security control: an eval suite tells you agents can use your tools correctly, not that a hostile agent cannot use them harmfully. Those are different questions, and only the first one has a harness.

Why this entry scored 20 out of 100

This profile starts at the catalog's neutral base of 50. Because the entry is officially published, trust adjusts the score by -40. Declared high-risk capabilities add +10 (capped at +30). It matches no dangerous capability combinations. The clamped result is 20, placing it in the low band.

See the full scoring formula →

Findings

  • Published by the vendor Trust offset
    Contribution to score: -40
  • 1 high-risk capability: filesystem:write High
    Contribution to score: +10

Capabilities

Every capability the entry declares, with the security implication of each.

  • browser:control Browser control
    Drives a browser session. Combined with credential access can impersonate the user on web services.
  • filesystem:write Filesystem write
    Can create, edit, or delete files on the host system. High-impact capability — anything from helpful edits to planting persistence.
  • network:outbound Outbound network
    Can make outbound network requests. Required for hosted model providers and remote APIs; also the path for data exfiltration if combined with read access.