Get recent messages from a Mattermost channel
AI agents call mattermost_get_channel_history to retrieve information from Mattermost MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool queries and retrieves existing channel message history. It performs a read-only operation that does not create, modify, delete, or execute any actions. The only risk is potential exposure of message content if the channel contains sensitive information, but this is a data access control issue rather than a capability risk of the tool itself.
From the tool's definition Tool name contains 'get' and description states 'Get recent messages from a Mattermost channel' — retrieves historical data with no modification or side effects.
Documented attack patterns abuse exactly the kind of access mattermost_get_channel_history gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Mattermost MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for mattermost_get_channel_history:
{
"version": "1",
"default": "deny",
"tools": {
"mattermost_get_channel_history": {}
}
}mattermost_get_channel_history is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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Get recent messages from a Mattermost channel. It is categorised as a Read tool in the Mattermost MCP Server MCP Server, which means it retrieves data without modifying state.
Register the Mattermost MCP Server MCP server in PolicyLayer and add a rule for mattermost_get_channel_history: 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 Mattermost MCP Server. Nothing to install.
mattermost_get_channel_history 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 mattermost_get_channel_history 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 mattermost_get_channel_history. 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.
mattermost_get_channel_history is provided by the Mattermost MCP Server MCP server (pvev/mattermost-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 9 Mattermost MCP Server tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
9 Mattermost MCP Server tools catalogued and risk-classified — across an index of 42,500+ MCP servers.