Time-travel snapshot: What was on your mind during a specific month?
AI agents call what_was_i_thinking to retrieve information from Brain without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This is a read-only query tool that retrieves historical cognitive state or conversation content indexed by the brain-mcp server. It takes a time period as input and returns stored embeddings/summaries—a classic Read category action with no side effects, reversibility concerns, or execution risks.
From the tool's definition Tool name 'what_was_i_thinking' and description 'Time-travel snapshot: What was on your mind during a specific month?' indicate a retrieval operation.
Documented attack patterns abuse exactly the kind of access what_was_i_thinking gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Brain, and nothing reaches the server without passing your rules. This is the rule we recommend for what_was_i_thinking:
{
"version": "1",
"default": "deny",
"tools": {
"what_was_i_thinking": {}
}
} what_was_i_thinking is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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Time-travel snapshot: What was on your mind during a specific month?. It is categorised as a Read tool in the Brain MCP Server, which means it retrieves data without modifying state.
Register the Brain MCP server in PolicyLayer and add a rule for what_was_i_thinking: 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 Brain. Nothing to install.
what_was_i_thinking is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the what_was_i_thinking 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 what_was_i_thinking. 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_was_i_thinking is provided by the Brain MCP server (mordechaipotash/brain-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Brain, 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.
34 Brain tools catalogued and risk-classified — across an index of 43,000+ MCP servers.