8 tools. 2 can modify or destroy data without limits.
2 write tools that can modify data. Rate limits recommended.
Last updated:
Write operations (slack_add_reaction, slack_post_message) modify state. Without rate limits, an agent can make hundreds of changes in seconds — faster than any human can review or revert.
Intercept sits between your agent and Slack User MCP Server. Every tool call checked against your policy before it executes — so your agent can do its job without breaking things.
npx -y @policylayer/intercept scan -- npx -y @lars-hagen/slack-user-mcp slack_add_reaction:
rules:
- rate_limit: 30/hour Prevents bulk unintended modifications from agents caught in loops.
slack_get_channel_history:
rules:
- rate_limit: 60/minute Controls API costs and prevents retry loops from exhausting upstream rate limits.
The Slack User MCP Server server has 2 write tools including slack_add_reaction, slack_post_message. Set rate limits in your policy file -- for example, rate_limit: 10/hour prevents an agent from making more than 10 modifications per hour. Intercept enforces this at the transport layer.
8 tools across 2 categories: Read, Write. 6 are read-only. 2 can modify, create, or delete data.
One line change. Instead of running the Slack User MCP Server server directly, prefix it with Intercept: intercept -c lars-hagen-slack-user-mcp.yaml -- npx -y @lars-hagen/slack-user-mcp. Download a pre-built policy from policylayer.com/policies/lars-hagen-slack-user-mcp and adjust the limits to match your use case.
Set budgets, approvals, and hard limits across MCP servers.
npx -y @policylayer/intercept init