get_willr
AI agents call get_willr to retrieve information from AlphaVantage MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
The tool appears to fetch the Williams %R (Willams Percent Range), a momentum technical indicator used in financial analysis. This is a read-only data retrieval operation with no capability to modify, delete, or execute code. The 'get_' prefix and similarity to other indicator tools on the same AlphaVantage server confirm the read classification.
From the tool's definition Tool name 'get_willr' follows the naming pattern of sibling tools (get_ad, get_adosc, get_adx, etc.), which are all technical indicator retrieval functions. 'get_' prefix indicates a read operation.
Attacks that exploit this kind of access
get_willr. It is categorised as a Read tool in the AlphaVantage MCP Server MCP Server, which means it retrieves data without modifying state.
Register the AlphaVantage MCP Server MCP server in PolicyLayer and add a rule for get_willr: 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 AlphaVantage MCP Server. Nothing to install.
get_willr 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 get_willr 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 get_willr. 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.
get_willr is provided by the AlphaVantage MCP Server MCP server (lifejwang11/alphavantage-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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