chat_completion · Openrouterai MCP: Risk & Policy

WHAT IT DOES

What chat_completion does on Openrouterai

AI agents invoke chat_completion to trigger actions in Openrouterai. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why chat_completion needs a policy

This tool executes an external API call to OpenRouter.ai, sending arbitrary messages to an AI model and returning generated text. It triggers external computation whose output depends entirely on the arguments passed. While it doesn't directly modify local data or move money, it invokes an external service (which may have associated costs and can produce arbitrary outputs), placing it firmly in Execute.

From the tool's definition Sends conversational context (messages) to OpenRouter.ai for completion using a specified model... triggers external operations whose effects depend on arguments

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

chat_completion Rate-limited

chat_completion stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "chat_completion": {
      "limits": [
        {
          "counter": "chat_completion_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Openrouterai, so you can run agents against it safely.

FAQ

Questions about chat_completion

What does the chat_completion tool do? +

Sends conversational context (messages) to OpenRouter.ai for completion using a specified model. Use this for dialogue, text generation, or instruction-following tasks. Supports advanced provider routing and parameter overrides. Returns the generated text response. It is categorised as a Execute tool in the Openrouterai MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on chat_completion? +

Register the Openrouterai MCP server in PolicyLayer and add a rule for chat_completion: 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 Openrouterai. Nothing to install.

What risk level is chat_completion? +

chat_completion is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit chat_completion? +

Yes. Add a rate_limit block to the chat_completion 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.

How do I block chat_completion completely? +

Set action: deny in the PolicyLayer policy for chat_completion. 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.

What MCP server provides chat_completion? +

chat_completion is provided by the Openrouterai MCP server (@mcpservers/openrouterai). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.