flake-update

Updates flake lock file inputs and returns structured information about what was updated.

SERVERHttp SOURCE@paretools/http

Medium RISK CLASS

Category Write

Parameters 00 required

Recommended Rate-limitedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/io-github-dave-london-http/flake-update.md

WHAT IT DOES

What flake-update does on Http

AI agents use flake-update to create or update resources in Http, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Http environment.

RISK

Why flake-update is rated Medium

This tool modifies lock files (likely Nix flake.lock), which is a reversible write operation. While it changes dependencies, the operation is not destructive (can be reverted via version control or re-locking) and doesn't delete data.

From the tool's definition Tool name 'flake-update' and description 'Updates flake lock file inputs' indicates modification of configuration/lock files. The phrase 'returns structured information about what was updated' confirms it writes changes.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs flake-update safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Http, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For flake-update, this is the rule to start with:

flake-update Rate-limited

flake-update 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "flake-update": {
      "limits": [
        {
          "counter": "flake-update_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Http, apply this rule, and every flake-update call is checked against it from then on.

FAQ

Questions about flake-update

What does the flake-update tool do? +

Updates flake lock file inputs and returns structured information about what was updated. It is categorised as a Write tool in the Http MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on flake-update? +

Register the Http MCP server in PolicyLayer and add a rule for flake-update: 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 Http. Nothing to install.

What risk level is flake-update? +

flake-update is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit flake-update? +

Yes. Add a rate_limit block to the flake-update 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 flake-update completely? +

Set action: deny in the PolicyLayer policy for flake-update. 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 flake-update? +

flake-update is provided by the Http MCP server (@paretools/http). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on Http, and thousands of servers like it.

This server

All 202 Http tools →

Across the catalogue

aroflo_create_or_update_record on AroFlo MCP →team_manager_update_budget on Team Manager MCP → The MCP Attack Database →

Guides

Govern customer-ops agents →Argument validation →Scoped token →