claim_signal · Agent Memory Bridge MCP: Risk & Policy

WHAT IT DOES

What claim_signal does on Agent Memory Bridge

AI agents use claim_signal to create or update resources in Agent Memory Bridge — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Agent Memory Bridge environment.

WHY IT NEEDS A POLICY

Why claim_signal needs a policy

The tool likely creates or modifies memory records by claiming ownership/reservation of a signal in the memory bridge. This is a write operation (reversible state change) rather than read-only retrieval. Without a description, confidence is moderate. Severity is medium because misuse could corrupt agent decision records or create locks, but effects are likely localized to this agent's memory context.

From the tool's definition Tool name 'claim_signal' suggests acquiring or reserving a signal in a memory system. Combined with sibling tools like 'extend_signal_lease' and 'store', this indicates state modification operations. The empty description limits certainty.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

claim_signal Rate-limited

claim_signal 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "claim_signal": {
      "limits": [
        {
          "counter": "claim_signal_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Agent Memory Bridge, so you can run agents against it safely.

FAQ

Questions about claim_signal

What does the claim_signal tool do? +

claim_signal. It is categorised as a Write tool in the Agent Memory Bridge MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on claim_signal? +

Register the Agent Memory Bridge MCP server in PolicyLayer and add a rule for claim_signal: 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 Agent Memory Bridge. Nothing to install.

What risk level is claim_signal? +

claim_signal is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit claim_signal? +

Yes. Add a rate_limit block to the claim_signal 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.

How do I block claim_signal completely? +

Set action: deny in the PolicyLayer policy for claim_signal. 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.

What MCP server provides claim_signal? +

claim_signal is provided by the Agent Memory Bridge MCP server (zzhang82/agent-memory-bridge). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.