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POST/api/v1/firewall/simulate

Simulate a firewall policy change (impact preview)

Policy Impact Simulator: before changing a firewall policy / sensitivity dial, dry-run the change against a set of sample (or recent) traffic and report what WOULD change — which inputs become newly-blocked, which become newly-allowed, verdict deltas, and the aggregate net block delta. Pure compute over the firewall engine (no DB write); each sample is scanned under both the current and proposed policy, with the engines built from the same sensitivityPreset + force-block logic /firewall/check uses. Caps: ≤200 samples, each ≤1,000,000 characters, whole request ≤16 MiB; changed samples echo back only the first 200 characters of the input. A policy is { sensitivity? (monitor|balanced|strict|lockdown or 1-4), forceBlockCategories?, rules? }; `proposed` is required, `current` defaults to the inline-check baseline. Requires gateway:read and the firewall:check scope.

Authentication

Send Authorization: Bearer YOUR_API_KEY on every request. Generate API keys at /dashboard/settings/api-keys.

Request body required

Example

{
  "samples": [],
  "current": {
    "forceBlockCategories": [
      "string"
    ],
    "rules": [
      "string"
    ]
  },
  "proposed": {
    "forceBlockCategories": [
      "string"
    ],
    "rules": [
      "string"
    ]
  },
  "projectId": "00000000-0000-0000-0000-000000000000"
}
Schema
{
  "application/json": {
    "schema": {
      "type": "object",
      "properties": {
        "samples": {
          "minItems": 1,
          "maxItems": 200,
          "type": "array",
          "items": {
            "anyOf": [
              {
                "type": "string",
                "minLength": 1,
                "maxLength": 1000000
              },
              {
                "type": "object",
                "properties": {
                  "input": {
                    "type": "string",
                    "minLength": 1,
                    "maxLength": 1000000
                  }
                },
                "required": [
                  "input"
                ],
                "additionalProperties": false
              }
            ]
          },
          "description": "Sample or recent traffic to evaluate (string or { input })."
        },
        "current": {
          "type": "object",
          "properties": {
            "sensitivity": {
              "anyOf": [
                {
                  "type": "string",
                  "enum": [
                    "monitor",
                    "balanced",
                    "strict",
                    "lockdown"
                  ]
                },
                {
                  "type": "integer",
                  "minimum": 1,
                  "maximum": 4
                }
              ]
            },
            "forceBlockCategories": {
              "maxItems": 20,
              "type": "array",
              "items": {
                "type": "string",
                "maxLength": 60
              }
            },
            "rules": {
              "maxItems": 50,
              "type": "array",
              "items": {
                "type": "string",
                "maxLength": 120
              }
            }
          },
          "additionalProperties": false
        },
        "proposed": {
          "type": "object",
          "properties": {
            "sensitivity": {
              "anyOf": [
                {
                  "type": "string",
                  "enum": [
                    "monitor",
                    "balanced",
                    "strict",
                    "lockdown"
                  ]
                },
                {
                  "type": "integer",
                  "minimum": 1,
                  "maximum": 4
                }
              ]
            },
            "forceBlockCategories": {
              "maxItems": 20,
              "type": "array",
              "items": {
                "type": "string",
                "maxLength": 60
              }
            },
            "rules": {
              "maxItems": 50,
              "type": "array",
              "items": {
                "type": "string",
                "maxLength": 120
              }
            }
          },
          "additionalProperties": false
        },
        "projectId": {
          "type": "string",
          "format": "uuid",
          "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$",
          "description": "Optional — used for org-scope resolution and telemetry only."
        }
      },
      "required": [
        "samples",
        "proposed"
      ],
      "additionalProperties": false
    }
  }
}

Response

200 example

{
  "success": true
}

All status codes

200Per-sample verdict diff + aggregate impact summary.
400(no description)
401(no description)
403Forbidden — the credential is valid but lacks the API-key scope, member role, or plan entitlement this operation requires.
429(no description)
500Internal Server Error — an unhandled error was converted to the standard error envelope (INTERNAL_ERROR).

Code samples

cURL

curl -X POST \
  https://evalguard.ai/api/v1/firewall/simulate \
  -H "Authorization: Bearer $EVALGUARD_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "samples": [], "current": { "forceBlockCategories": [ "string" ], "rules": [ "string" ] }, "proposed": { "forceBlockCategories": [ "string" ], "rules": [ "string" ] }, "projectId": "00000000-0000-0000-0000-000000000000" }'

TypeScript

// The TypeScript SDK (@evalguard/sdk) exposes TYPED methods — runEval,
// getEval, runSecurityScan, checkFirewall, … — not a generic request().
// For an arbitrary endpoint, call it directly:

const res = await fetch("https://evalguard.ai/api/v1/firewall/simulate", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.EVALGUARD_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "samples": [],
    "current": {
      "forceBlockCategories": [
        "string"
      ],
      "rules": [
        "string"
      ]
    },
    "proposed": {
      "forceBlockCategories": [
        "string"
      ],
      "rules": [
        "string"
      ]
    },
    "projectId": "00000000-0000-0000-0000-000000000000"
  }),
});
console.log(res.status, await res.json());

Python

# The Python SDK (pip install evalguardai) exposes TYPED methods on
# EvalGuardClient — run_eval, get_eval, … — not a generic request().
# For an arbitrary endpoint, call it directly:

import os
import requests

headers = {"Authorization": f"Bearer {os.environ['EVALGUARD_API_KEY']}"}
headers["Content-Type"] = "application/json"

response = requests.request(
    "POST",
    "https://evalguard.ai/api/v1/firewall/simulate",
    headers=headers,
    json={
    "samples": [],
    "current": {
        "forceBlockCategories": [
            "string"
        ],
        "rules": [
            "string"
        ]
    },
    "proposed": {
        "forceBlockCategories": [
            "string"
        ],
        "rules": [
            "string"
        ]
    },
    "projectId": "00000000-0000-0000-0000-000000000000"
},
)
print(response.status_code, response.json())

Go

package main

import (
	"context"
	"fmt"
	"net/http"
	"os"
	"strings"
)

func main() {
	body := strings.NewReader(`{"samples":[],"current":{"forceBlockCategories":["string"],"rules":["string"]},"proposed":{"forceBlockCategories":["string"],"rules":["string"]},"projectId":"00000000-0000-0000-0000-000000000000"}`)
	req, _ := http.NewRequestWithContext(context.Background(), "POST", "https://evalguard.ai/api/v1/firewall/simulate", body)
	req.Header.Set("Authorization", "Bearer "+os.Getenv("EVALGUARD_API_KEY"))
	req.Header.Set("Content-Type", "application/json")
	resp, err := http.DefaultClient.Do(req)
	if err != nil { panic(err) }
	defer resp.Body.Close()
	fmt.Println(resp.Status)
}

Errors

400401403429500

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