Add, save, store, or remember information to the project memory. Use this when the user wants to remember something, save a preference, store a decision, or add a note for later. Keywords: add, save, store, remember, note, record, keep.
AI agents use memory_write to create or update resources in Copilot Memory Store — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Copilot Memory Store environment.
This tool creates or modifies data (memories) in a reversible manner. It does not delete data (which would be Destructive), execute code (Execute), or move money (Financial). It is a standard Write operation that allows an agent to persist information.
From the tool's definition Tool description explicitly states: 'Add, save, store, or remember information to the project memory.' Keywords include 'add, save, store, remember, note, record, keep' — all indicative of creating or modifying data.
Documented attack patterns abuse exactly the kind of access memory_write gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Copilot Memory Store, and nothing reaches the server without passing your rules. This is the rule we recommend for memory_write:
{
"version": "1",
"default": "deny",
"tools": {
"memory_write": {
"limits": [
{
"counter": "memory_write_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}memory_write 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.
Free to start. No card required.
Add, save, store, or remember information to the project memory. Use this when the user wants to remember something, save a preference, store a decision, or add a note for later. Keywords: add, save, store, remember, note, record, keep. It is categorised as a Write tool in the Copilot Memory Store MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Copilot Memory Store MCP server in PolicyLayer and add a rule for memory_write: 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 Copilot Memory Store. Nothing to install.
memory_write 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_write 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_write. 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_write is provided by the Copilot Memory Store MCP server (timothywarner-org/copilot-memory-store). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Copilot Memory Store, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
7 Copilot Memory Store tools catalogued and risk-classified — across an index of 43,000+ MCP servers.