Generate a histogram chart to show the frequency of data points within a certain range. It can observe data distribution, such as, normal and skewed distributions, and identify data concentration areas and extreme points.
AI agents use generate_histogram_chart to create or update resources in Chart Offline — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Chart Offline environment.
This tool generates chart visualizations from input data. While it produces output (making it a 'Write' action rather than a pure 'Read'), the output is a new SVG chart visualization with no side effects on underlying systems, data stores, or external services. The server is explicitly described as 'fully offline' with 'no network dependency,' eliminating Execute or Financial risks.
From the tool's definition Tool name contains 'generate' and description states it produces a histogram chart (an SVG output). The tool creates new chart data/visualization artifacts without modifying or deleting existing data.
Documented attack patterns abuse exactly the kind of access generate_histogram_chart gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Chart Offline, and nothing reaches the server without passing your rules. This is the rule we recommend for generate_histogram_chart:
{
"version": "1",
"default": "deny",
"tools": {
"generate_histogram_chart": {
"limits": [
{
"counter": "generate_histogram_chart_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}generate_histogram_chart 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.
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Generate a histogram chart to show the frequency of data points within a certain range. It can observe data distribution, such as, normal and skewed distributions, and identify data concentration areas and extreme points. It is categorised as a Write tool in the Chart Offline MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Chart Offline MCP server in PolicyLayer and add a rule for generate_histogram_chart: 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 Chart Offline. Nothing to install.
generate_histogram_chart 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 generate_histogram_chart 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 generate_histogram_chart. 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.
generate_histogram_chart is provided by the Chart Offline MCP server (liukeyu800/mcp-server-chart-offline). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Chart Offline, 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.
15 Chart Offline tools catalogued and risk-classified — across an index of 43,000+ MCP servers.