Subscribe to or change your Disco plan. Available plans: - "free_tier": Explorer — free, 10 credits/month - "tier_1": Researcher — $49/month, 500 credits/month - "tier_2": Team — $199/month, 2000 credits/month Paid plans require a payment method on file. Credits roll over on paid plans. Args: pla...
Risk signalsHandles credentials or secrets (api_key)
Part of the Discovery Engine server.
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AI agents use discovery_subscribe to create or modify resources in Discovery Engine. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.
Without a policy, an AI agent could call discovery_subscribe repeatedly, creating or modifying resources faster than any human could review. PolicyLayer's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach Discovery Engine.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"discovery_subscribe": {
"limits": [
{
"counter": "discovery_subscribe_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full Discovery Engine policy for all 14 tools.
These attack patterns abuse exactly the kind of access discovery_subscribe gives an agent. Each links to the full case and the policy that stops it:
Other write tools across the catalogue. The same approach applies to each: rate-limit and validate the arguments.
Subscribe to or change your Disco plan. Available plans: - "free_tier": Explorer — free, 10 credits/month - "tier_1": Researcher — $49/month, 500 credits/month - "tier_2": Team — $199/month, 2000 credits/month Paid plans require a payment method on file. Credits roll over on paid plans. Args: plan: Plan tier ID ("free_tier", "tier_1", or "tier_2"). api_key: Disco API key (disco_...). Optional if DISCOVERY_API_KEY env var is set.. It is categorised as a Write tool in the Discovery Engine MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Discovery Engine MCP server in PolicyLayer and add a rule for discovery_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 Discovery Engine. Nothing to install.
discovery_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 discovery_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 discovery_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.
discovery_subscribe is provided by the Discovery Engine MCP server (leap-laboratories/discovery-engine). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 14 Discovery Engine tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
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