Store a thought with schema-enforced metadata. Handles dedup, conflict detection, and supersedes relations. Pass
AI agents use agent_capture to create or update resources in Mybrain — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Mybrain environment.
The tool creates/stores new data (thoughts) in PostgreSQL. It handles deduplication and supersedes relations, indicating it writes and may update existing entries. While it can overwrite or supersede prior records, these actions appear reversible (records remain in DB with relations), placing it in Write rather than Destructive.
From the tool's definition 'Store a thought with schema-enforced metadata. Handles dedup, conflict detection, and supersedes relations.'
Documented attack patterns abuse exactly the kind of access agent_capture gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Mybrain, and nothing reaches the server without passing your rules. This is the rule we recommend for agent_capture:
{
"version": "1",
"default": "deny",
"tools": {
"agent_capture": {
"limits": [
{
"counter": "agent_capture_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}agent_capture 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.
Store a thought with schema-enforced metadata. Handles dedup, conflict detection, and supersedes relations. Pass. It is categorised as a Write tool in the Mybrain MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Mybrain MCP server in PolicyLayer and add a rule for agent_capture: 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 Mybrain. Nothing to install.
agent_capture 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 agent_capture 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 agent_capture. 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.
agent_capture is provided by the Mybrain MCP server (robertsfeir/mybrain). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Mybrain, 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.
8 Mybrain tools catalogued and risk-classified — across an index of 43,000+ MCP servers.