Create a proactive monitoring subscription to a live-data event stream. Returns the new subscription id. Requires a Pipeworx OAuth account (anonymous + BYO cannot persist subscriptions). Supported types: "sec_8k" (8-K filings matching ticker + item codes — e.g. items:["5.02"] = officer change), "...
AI agents use subscribe to create or update resources in Mcp Celestrak — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Mcp Celestrak environment.
| Parameter | Type | Required | Description |
|---|---|---|---|
type | string | Yes | Subscription type. |
params | object | Yes | Type-specific filter. sec_8k: {ticker:"AAPL", items?:["5.02","1.01"]}. polymarket_edge: {topic:"fed", min_spread_bps?:500}. fred_series: {series_id:"UNRATE"}. p |
delivery | object | — | Optional delivery channels in addition to the always-on persistent feed. {email:"you@x.com"} sends a templated alert per fired event. {sms:"+15551234567"} sends |
Parameters from the server's own tool schema.
The tool creates and stores a new subscription object in a backend system, which is a reversible write operation. While subscriptions can typically be deleted or modified later, the act of creating one modifies persistent state.
From the tool's definition Tool name is 'subscribe' and description states 'Create a proactive monitoring subscription to a live-data event stream. Returns the new subscription id.' This is a create operation that generates and persists a new subscription resource.
Risk signalsAccepts URL/endpoint input (delivery.webhook)
Attacks that exploit this kind of access
Create a proactive monitoring subscription to a live-data event stream. Returns the new subscription id. Requires a Pipeworx OAuth account (anonymous + BYO cannot persist subscriptions). Supported types: "sec_8k" (8-K filings matching ticker + item codes — e.g. items:["5.02"] = officer change), "polymarket_edge" (Polymarket↔Kalshi cross-venue mispricings — params:{topic:"fed"}), "fred_series" (new FRED observations — params:{series_id:"UNRATE"}). Delivery channels: feed (always on — pull via recent_alerts or GET registry.pipeworx.io/alerts.json), and optionally email (set delivery:{email:"you@x.com"}) or sms (delivery:{sms:"+15551234567"} — phone must be verified at /account first; 10/day cap). It is categorised as a Write tool in the Mcp Celestrak MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
subscribe accepts 3 parameters: type, params, delivery. Required: type, params. The full parameter table on this page comes from the server's own tool schema.
Register the Mcp Celestrak MCP server in PolicyLayer and add a rule for subscribe: 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 Mcp Celestrak. Nothing to install.
subscribe is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the subscribe 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 subscribe. 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.
subscribe is provided by the Mcp Celestrak MCP server (pipeworx-io/mcp-celestrak). 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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