github_graphql · Promethean OS MCP: Risk & Policy

WHAT IT DOES

What github_graphql does on Promethean OS MCP

AI agents invoke github_graphql to trigger actions in Promethean OS MCP. 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 github_graphql needs a policy

GraphQL mutations can create, modify, or delete GitHub resources (repos, issues, PRs, branches, etc.), not just read data. Since the tool posts arbitrary GraphQL queries, it spans Read through Destructive operations depending on the query content. The most severe applicable category is Execute, as it triggers external operations on GitHub whose effects are fully argument-dependent.

From the tool's definition Post a GraphQL query to GitHub

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

github_graphql Rate-limited

github_graphql 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": {
    "github_graphql": {
      "limits": [
        {
          "counter": "github_graphql_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 Promethean OS MCP, so you can run agents against it safely.

FAQ

Questions about github_graphql

What does the github_graphql tool do? +

Post a GraphQL query to GitHub. It is categorised as a Execute tool in the Promethean OS MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on github_graphql? +

Register the Promethean OS MCP server in PolicyLayer and add a rule for github_graphql: 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 Promethean OS MCP. Nothing to install.

What risk level is github_graphql? +

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

Can I rate-limit github_graphql? +

Yes. Add a rate_limit block to the github_graphql 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 github_graphql completely? +

Set action: deny in the PolicyLayer policy for github_graphql. 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 github_graphql? +

github_graphql is provided by the Promethean OS MCP server (octave-commons/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.