Store a fact in memory. Use dot-separated keypaths.
AI agents use memory_store to create or update resources in Memstate AI - Agent Memory System — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Memstate AI - Agent Memory System environment.
This tool writes data to a versioned memory store. It is reversible in the sense that memory history is tracked (sibling tool memory_history exists), so it is not Destructive. It modifies persistent state for an AI agent, giving it medium severity since incorrect or malicious writes could corrupt an agent's knowledge base or introduce false facts that influence future behavior.
From the tool's definition 'Store a fact in memory' — creates or modifies structured memory entries using dot-separated keypaths
Attacks that exploit this kind of access
Store a fact in memory. Use dot-separated keypaths. It is categorised as a Write tool in the Memstate AI - Agent Memory System MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Memstate AI - Agent Memory System MCP server in PolicyLayer and add a rule for memory_store: 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 Memstate AI - Agent Memory System. Nothing to install.
memory_store 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 memory_store 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 memory_store. 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.
memory_store is provided by the Memstate AI - Agent Memory System MCP server (memstate-ai/memstate-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
memory_store is one line of Memstate AI - Agent Memory System's registry record.
The record carries the whole server: verified identity, auth posture, risk grade, every tool classified, recommended policy — re-checked continuously.
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