The Hilbert Transform Dominant Cycle Period (HT_DCPERIOD) identifies the dominant market cycle length, helping traders adapt their strategies to different market conditions. You can read more about it in the Rocket Science for Traders book by John F. Ehlers.
AI agents call GetTimeSeriesHtDcPeriod to retrieve information from Twelve Data MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool performs a read-only calculation on financial time series data to derive a technical indicator. It retrieves or computes information without side effects, modifying data, executing arbitrary code, or affecting financial positions. This is a classic analytical read operation common in financial data APIs.
From the tool's definition Tool retrieves and calculates the Hilbert Transform Dominant Cycle Period, which is a technical analysis metric derived from market data.
Documented attack patterns abuse exactly the kind of access GetTimeSeriesHtDcPeriod gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Twelve Data MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for GetTimeSeriesHtDcPeriod:
{
"version": "1",
"default": "deny",
"tools": {
"GetTimeSeriesHtDcPeriod": {}
}
}GetTimeSeriesHtDcPeriod is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
The Hilbert Transform Dominant Cycle Period (HT_DCPERIOD) identifies the dominant market cycle length, helping traders adapt their strategies to different market conditions. You can read more about it in the Rocket Science for Traders book by John F. Ehlers. It is categorised as a Read tool in the Twelve Data MCP Server MCP Server, which means it retrieves data without modifying state.
Register the Twelve Data MCP Server MCP server in PolicyLayer and add a rule for GetTimeSeriesHtDcPeriod: 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 Twelve Data MCP Server. Nothing to install.
GetTimeSeriesHtDcPeriod 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 GetTimeSeriesHtDcPeriod 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 GetTimeSeriesHtDcPeriod. 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.
GetTimeSeriesHtDcPeriod is provided by the Twelve Data MCP Server MCP server (twelvedata/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 186 Twelve Data MCP Server tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
186 Twelve Data MCP Server tools catalogued and risk-classified — across an index of 42,500+ MCP servers.