Register an agent with the ACR network. Optional — agents are auto-registered on first tool call. The MCP owns the Ed25519 keypair used for proof-of-possession; the agent never handles keys directly. ACR collects interaction metadata (target names, timing, status) to build your interaction profil...
Risk signalsHigh parameter count (17 properties)
Part of the ACR — Agent Composition Records server.
Free to start. No card required.
AI agents use register_agent to create or modify resources in ACR — Agent Composition Records. 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 register_agent 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 ACR — Agent Composition Records.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"register_agent": {
"limits": [
{
"counter": "register_agent_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full ACR — Agent Composition Records policy for all 30 tools.
These attack patterns abuse exactly the kind of access register_agent 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.
Register an agent with the ACR network. Optional — agents are auto-registered on first tool call. The MCP owns the Ed25519 keypair used for proof-of-possession; the agent never handles keys directly. ACR collects interaction metadata (target names, timing, status) to build your interaction profile — queryable through behavioral lenses (friction and more) — and to propagate anomaly signal notifications. No request/response content is collected. We do not track the agent owner. Terms: https://acr.nfkey.ai/terms. It is categorised as a Write tool in the ACR — Agent Composition Records MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the ACR — Agent Composition Records MCP server in PolicyLayer and add a rule for register_agent: 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 ACR — Agent Composition Records. Nothing to install.
register_agent 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 register_agent 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 register_agent. 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.
register_agent is provided by the ACR — Agent Composition Records MCP server (@tethral/acr-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 30 ACR — Agent Composition Records tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
4,600+ MCP servers and 31,000+ tools scanned and risk-classified.