This server provides an MCP tool hejdar_evaluate that lets any MCP-compatible AI agent check whether an intended action is permitted by organizational security policies before executing it.
Evaluate actions of types READ, WRITE, DELETE, TRANSFER, or EXECUTE (UPDATE accepted as alias for WRITE) against Hejdar policies.
Supply the target resource (e.g. customer_database) and optionally the agent name and free-form context (department, user_id, reason, etc.).
Receive a decision of ALLOW, DENY, or WOULD_DENY, along with policy ID, reason, and risk level.
Integrate easily with Claude Desktop, Claude Code, or any stdio-based MCP client via uvx hejdar-mcp.
Use the recommended system prompt pattern to enforce mandatory policy checks before sensitive actions.
Configure via environment variables: HEJDAR_API_KEY (required) and HEJDAR_API_URL (optional for self-hosted API).
MCP server for Hejdar — runtime policy enforcement for AI agents.
This server exposes hejdar_evaluate as an MCP tool. Any MCP-compatible agent (Claude, ChatGPT, Cursor, custom) can call it to check whether an action is permitted by organizational policy before executing it.
The MCP server is a thin wrapper around the Hejdar API (POST /v1/evaluate). It contains no policy logic — all decisions come from your Hejdar organization's configured policies.
pip install hejdar-mcpOr run directly with uvx:
uvx hejdar-mcpSign up at app.hejdar.com and create an API key in Settings → API Keys.
Add to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json on macOS, %APPDATA%\Claude\claude_desktop_config.json on Windows):
{
"mcpServers": {
"hejdar": {
"command": "uvx",
"args": ["hejdar-mcp"],
"env": {
"HEJDAR_API_KEY": "hejdar_sk_your_key_here"
}
}
}
}Add to your Claude Code MCP settings:
{
"mcpServers": {
"hejdar": {
"command": "uvx",
"args": ["hejdar-mcp"],
"env": {
"HEJDAR_API_KEY": "hejdar_sk_your_key_here"
}
}
}
}export HEJDAR_API_KEY=hejdar_sk_your_key_here
hejdar-mcpRelated MCP server: aegis
Install: pip install hejdar-mcp or uvx hejdar-mcp
Get an API key — contact us at hello@hejdar.com or visit hejdar.com
Configure your MCP client (see configuration example above)
hejdar_evaluateEvaluate an agent action against your organization's security policies.
Input:
Parameter | Type | Required | Description |
| string | Yes |
|
| string | Yes | Target resource, e.g. |
| string | No | Name of the calling agent, e.g. |
| object | No | Free-form metadata (department, user_id, reason, etc.) |
Output:
{
"decision": "DENY",
"policy_id": "pol_abc123",
"reason": "Deletion of customer data requires manager approval",
"risk_level": "HIGH"
}decision is one of: ALLOW, DENY, WOULD_DENY.
For best results, add this to your agent's system prompt:
You have access to the hejdar_evaluate tool. Before performing any action
that reads, writes, deletes, transfers data, or executes commands on
external systems, you MUST call hejdar_evaluate first.
If hejdar_evaluate returns DENY or WOULD_DENY, do NOT proceed with the
action. Instead, inform the user that the action was blocked by policy
and include the reason provided.Variable | Required | Default | Description |
| Yes | — | Your Hejdar API key |
| No |
| API base URL (for self-hosted) |
API key is read from environment variables only — never hardcoded or exposed in tool I/O
All inputs are validated and sanitized before forwarding to the API
Error responses never leak internal details, API keys, or stack traces
All API calls enforce TLS
git clone https://github.com/ARKALDA/hejdar-mcp.git
cd hejdar-mcp
pip install -e ".[dev]"
pytestMIT
Evaluate an AI agent action against Hejdar security policies BEFORE executing it. Returns ALLOW, DENY, or WOULD_DENY. Call this before any sensitive action (read, write, delete, transfer, execute) to check if the action is permitted by organizational policy. If the decision is DENY, do NOT execute the action.
Inputs: action_type (required), resource (required), agent_name, context.
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
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Scored across 1 tool
With only one tool, there is no possibility of ambiguity or overlap with other tools. The tool's purpose is clearly defined as evaluating AI agent actions against security policies, making it distinct and unambiguous in isolation.
A single tool inherently has perfect naming consistency since there are no other tools to compare against. The name 'hejdar_evaluate' follows a clear pattern of server prefix and action, which would be consistent if more tools existed.
A single tool is too few for a server that claims to handle security policy evaluation across various actions (read, write, delete, transfer, execute). This minimal set forces agents to rely solely on this one tool without dedicated tools for different policy aspects or actions, making the scope feel incomplete and thin.
The server's domain appears to be security policy evaluation for AI actions, but with only one tool, there are significant gaps. It lacks tools for managing policies, querying specific rules, or handling different types of security checks, which limits agents to a single evaluation call without supporting operations for a comprehensive workflow.
Deterministic runtime safety for AI agents: scan PII, gate tool actions, verify LLM output.
Security gateway for AI agents: policy, approval, and audited execution, no secrets shared.
See, price, and control every tool call your AI agents make: policy checks, cost, and audit tools.
Zero-trust gateway for AI agents: score tool calls, verify agent cards, enforce policy, audit.
