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POST/api/v1/mcp/invoke

Invoke an MCP server tool

Gateway endpoint for invoking a tool on a registered Model Context Protocol (MCP) server. Validates JWT (when server.authType='jwt'), enforces per-tool RBAC against mcp_tool_permissions.allowed_roles, applies sliding-window rate-limit per (server, tool), and forwards to the upstream server. Every invocation (allow/deny/error) is recorded to mcp_tool_invocations for audit.

Authentication

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

Request body required

Example

{
  "serverId": "<mcp_servers.id>",
  "toolName": "<Tool name registered on the server>",
  "arguments": {},
  "jwt": "<Bearer JWT when server.authType='jwt'>",
  "taskGoal": "string",
  "clientId": "string",
  "cimdJws": "string",
  "cimdNonce": "string",
  "projectId": "00000000-0000-0000-0000-000000000000",
  "agentId": "string"
}
Schema
{
  "application/json": {
    "schema": {
      "type": "object",
      "properties": {
        "serverId": {
          "type": "string",
          "minLength": 1,
          "maxLength": 200,
          "description": "mcp_servers.id"
        },
        "toolName": {
          "type": "string",
          "minLength": 1,
          "maxLength": 200,
          "description": "Tool name registered on the server"
        },
        "arguments": {
          "type": "object",
          "additionalProperties": {},
          "description": "Tool-specific arguments forwarded to upstream"
        },
        "jwt": {
          "type": "string",
          "maxLength": 20000,
          "description": "Bearer JWT when server.authType='jwt'"
        },
        "taskGoal": {
          "type": "string",
          "maxLength": 4000
        },
        "clientId": {
          "type": "string",
          "maxLength": 2048
        },
        "cimdJws": {
          "type": "string",
          "maxLength": 20000
        },
        "cimdNonce": {
          "type": "string",
          "maxLength": 512
        },
        "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)$"
        },
        "agentId": {
          "type": "string",
          "minLength": 1,
          "maxLength": 200
        }
      },
      "required": [
        "serverId",
        "toolName"
      ],
      "additionalProperties": {}
    }
  }
}

Response

200 example

{
  "success": true
}

All status codes

200Tool invoked successfully.
400(no description)
401(no description)
403Forbidden — caller's role not in tool's allowed_roles, or JWT validation failed.
404Server or tool permission row not found.
429(no description)
501Transport not implemented (only HTTP transport forwards today; stdio/SSE/WS still audit-log but return 501).

Code samples

cURL

curl -X POST \
  https://evalguard.ai/api/v1/mcp/invoke \
  -H "Authorization: Bearer $EVALGUARD_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "serverId": "<mcp_servers.id>", "toolName": "<Tool name registered on the server>", "arguments": {}, "jwt": "<Bearer JWT when server.authType='jwt'>", "taskGoal": "string", "clientId": "string", "cimdJws": "string", "cimdNonce": "string", "projectId": "00000000-0000-0000-0000-000000000000", "agentId": "string" }'

TypeScript

import { EvalGuard } from "@evalguard/sdk";

const client = new EvalGuard({ apiKey: process.env.EVALGUARD_API_KEY });

const response = await client.request({
  method: "POST",
  path: "/api/v1/mcp/invoke",
  body: {
    "serverId": "<mcp_servers.id>",
    "toolName": "<Tool name registered on the server>",
    "arguments": {},
    "jwt": "<Bearer JWT when server.authType='jwt'>",
    "taskGoal": "string",
    "clientId": "string",
    "cimdJws": "string",
    "cimdNonce": "string",
    "projectId": "00000000-0000-0000-0000-000000000000",
    "agentId": "string"
  },
});
console.log(response);

Python

from evalguard import EvalGuard
import os

client = EvalGuard(api_key=os.environ["EVALGUARD_API_KEY"])

response = client.request(
    method="POST",
    path="/api/v1/mcp/invoke",
    body={
    "serverId": "<mcp_servers.id>",
    "toolName": "<Tool name registered on the server>",
    "arguments": {},
    "jwt": "<Bearer JWT when server.authType='jwt'>",
    "taskGoal": "string",
    "clientId": "string",
    "cimdJws": "string",
    "cimdNonce": "string",
    "projectId": "00000000-0000-0000-0000-000000000000",
    "agentId": "string"
},
)
print(response)

Go

package main

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

func main() {
	body := strings.NewReader(`{"serverId":"<mcp_servers.id>","toolName":"<Tool name registered on the server>","arguments":{},"jwt":"<Bearer JWT when server.authType='jwt'>","taskGoal":"string","clientId":"string","cimdJws":"string","cimdNonce":"string","projectId":"00000000-0000-0000-0000-000000000000","agentId":"string"}`)
	req, _ := http.NewRequestWithContext(context.Background(), "POST", "https://evalguard.ai/api/v1/mcp/invoke", 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

400401403404429501

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