pt_subscribe
Subscribe to a channel by handle (name@host). Rate-limited: 30/hour.
This record as markdown: /tools/kh0pper-crow/pt-subscribe.md
What pt_subscribe does on Crow
AI agents use pt_subscribe to create or update resources in Crow, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Crow environment.
Why pt_subscribe is rated Medium
Subscribing to a channel creates a new subscription relationship/record on the platform, which is a reversible write operation. It does not delete data, execute code, or move money. The rate limiting (30/hour) suggests it triggers external operations but primarily registers a follow/subscription state. Severity is medium as misuse could result in unwanted subscriptions across many channels.
From the tool's definition Subscribe to a channel by handle (name@host)
Attacks that exploit this kind of access
The rule that runs pt_subscribe safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Crow, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For pt_subscribe, this is the rule to start with:
pt_subscribe stays usable, but capped: an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Crow, apply this rule, and every pt_subscribe call is checked against it from then on.
Questions about pt_subscribe
Subscribe to a channel by handle (name@host). Rate-limited: 30/hour. It is categorised as a Write tool in the Crow MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Crow MCP server in PolicyLayer and add a rule for pt_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 Crow. Nothing to install.
pt_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 pt_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 pt_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.
pt_subscribe is provided by the Crow MCP server (kh0pper/crow). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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