send_agent_message
Send a focused message to a descendant child agent or to a named teammate in the current persistent bot team.
This record as markdown: /tools/cowork-os/send-agent-message.md
What send_agent_message does on CoWork OS
AI agents use send_agent_message to create or update resources in CoWork OS, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your CoWork OS environment.
Why send_agent_message is rated Medium
Creates new messages in a persistent system but lacks destructive or financial impact; moderate misuse risk.
From the tool's definition Send message to descendant child agent or named teammate; creates communication artifact.
Attacks that exploit this kind of access
The rule that runs send_agent_message safely
PolicyLayer is an MCP gateway: it sits between your AI agents and CoWork OS, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For send_agent_message, this is the rule to start with:
send_agent_message 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.
The button opens the PolicyLayer dashboard: create your workspace, connect CoWork OS, apply this rule, and every send_agent_message call is checked against it from then on.
Questions about send_agent_message
Send a focused message to a descendant child agent or to a named teammate in the current persistent bot team. It is categorised as a Write tool in the CoWork OS MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the CoWork OS MCP server in PolicyLayer and add a rule for send_agent_message: 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 CoWork OS. Nothing to install.
send_agent_message 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 send_agent_message 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 send_agent_message. 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.
send_agent_message is provided by the CoWork OS MCP server (CoWork-OS/CoWork-OS). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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