Check browser compatibility for a specific web platform feature using MDN Browser Compat Data (BCD). Returns version support across browsers, Baseline status, and links to MDN/spec documentation. Args: - feature (string): BCD identifier in dot notation (e.g.,
AI agents call compat_check to retrieve information from Web Compat without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
The compat_check tool retrieves browser compatibility information from MDN Browser Compat Data (BCD) based on a feature identifier. It returns read-only data (version support, status, documentation links) with no side effects, data modification, code execution, or destructive operations. This is a straightforward data retrieval operation.
From the tool's definition Tool description states it 'Check[s] browser compatibility' and 'Returns version support across browsers, Baseline status, and links to MDN/spec documentation.' These are purely informational read operations that query and retrieve data without modification.
Attacks that exploit this kind of access
Check browser compatibility for a specific web platform feature using MDN Browser Compat Data (BCD). Returns version support across browsers, Baseline status, and links to MDN/spec documentation. Args: - feature (string): BCD identifier in dot notation (e.g.,. It is categorised as a Read tool in the Web Compat MCP Server, which means it retrieves data without modifying state.
Register the Web Compat MCP server in PolicyLayer and add a rule for compat_check: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Web Compat. Nothing to install.
compat_check is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the compat_check rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for compat_check. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
compat_check is provided by the Web Compat MCP server (shuji-bonji/web-compat-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
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