# io.github.kanywst/mcp-opa-authz (oci · ghcr.io/kanywst/mcp-opa-authz:0.3.0)

Authorization answers from real policy code: evaluate Rego locally, or ask an AuthZEN 1.0 PDP.

- Trust score: 44/100 (low)
- Change this week: +4
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-09-20

## Components

- oci · `ghcr.io/kanywst/mcp-opa-authz:0.3.0`: 44/100 (this document), [markdown](https://verifymcp.io/servers/kanywst-mcp-opa-authz/ghcr-io-kanywst-mcp-opa-authz-0-3-0.md), [page](https://verifymcp.io/servers/kanywst-mcp-opa-authz/ghcr-io-kanywst-mcp-opa-authz-0-3-0)

## Channel facts

- Registry: `oci`
- Package: `ghcr.io/kanywst/mcp-opa-authz:0.3.0`
- Transport: `stdio`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-09-20.

- **Supply Chain Security**: 0/100
  - Malware scan not yet available for this package.
  - Known CVEs could not be checked: this artifact ships no SBOM, so there is no dependency list to read. Publishing one would let us assess it.
  - Install-script risk not yet assessed.
  - Dependency health could not be checked: this artifact ships no SBOM, so there is no dependency list to read. Publishing one would let us assess it.
- **Provenance & Transparency**: 48/100
  - Source repository is publicly reachable at the declared URL.
  - Provenance check failed: no build-provenance attestation is published.
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 8 days ago).
  - Publishes a security disclosure policy (SECURITY.md).
- **Schema Quality & AI Usability**: 69/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 1202 tokens (~300/item across 4 items; 4 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 30/100
  - Stability observed for 9 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
  - Structured output schemas are declared (100% of tools); any adoption earns full credit.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 4 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 5 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a current MCP spec version (2026-07-28).

**Unverified: 1 category.** A category scored 0 because we could not verify it: a data source with nothing on this package, evidence we could not reach, or a check we could not run. We only credit what we can confirm.

## Install

### How do I install the io.github.kanywst/mcp-opa-authz server?

io.github.kanywst/mcp-opa-authz runs locally as a container image, launched with docker run --rm -i ghcr.io/kanywst/mcp-opa-authz:0.3.0. Ready-made configuration for Claude, Cursor, VS Code, Codex and 3 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add kanywst-mcp-opa-authz -- docker run --rm -i ghcr.io/kanywst/mcp-opa-authz:0.3.0
```

### Cursor

```json
{
  "mcpServers": {
    "kanywst-mcp-opa-authz": {
      "command": "docker",
      "args": [
        "run",
        "--rm",
        "-i",
        "ghcr.io/kanywst/mcp-opa-authz:0.3.0"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "kanywst-mcp-opa-authz": {
      "command": "docker",
      "args": [
        "run",
        "--rm",
        "-i",
        "ghcr.io/kanywst/mcp-opa-authz:0.3.0"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add kanywst-mcp-opa-authz -- docker run --rm -i ghcr.io/kanywst/mcp-opa-authz:0.3.0
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "kanywst-mcp-opa-authz": {
      "type": "local",
      "command": [
        "docker",
        "run",
        "--rm",
        "-i",
        "ghcr.io/kanywst/mcp-opa-authz:0.3.0"
      ],
      "enabled": true
    }
  }
}
```

### Hermes

```yaml
mcp_servers:
  kanywst-mcp-opa-authz:
    command: "docker"
    args: ["run", "--rm", "-i", "ghcr.io/kanywst/mcp-opa-authz:0.3.0"]
```

### Netclaw

```json
{
  "McpServers": {
    "kanywst-mcp-opa-authz": {
      "Transport": "stdio",
      "Command": "docker",
      "Arguments": [
        "run",
        "--rm",
        "-i",
        "ghcr.io/kanywst/mcp-opa-authz:0.3.0"
      ]
    }
  }
}
```

### Other

```json
{
  "mcpServers": {
    "kanywst-mcp-opa-authz": {
      "command": "docker",
      "args": [
        "run",
        "--rm",
        "-i",
        "ghcr.io/kanywst/mcp-opa-authz:0.3.0"
      ]
    }
  }
}
```

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-09-19 (score 44, +1)

No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-09-18 (score 43, +3)

- [functional improvement] Stability: unverified → 0.23

### 2026-09-11 (score 40)

First indexed and scored.

## MCP tools (4)

### `authzen_discover` (~118 tokens)

Fetch a PDP's AuthZEN metadata document from /.well-known/authzen-configuration to find out which endpoints and capabilities it offers. Use this when a PDP URL is known but its evaluation endpoint is not, or to check whether a PDP supports batch evaluation before calling authzen_evaluate_batch.

Input parameters:

- `pdp_url` (string): The PDP root, e.g. `https://pdp.example.com`. An evaluation endpoint URL is also accepted — the known AuthZEN path suffix is stripped. Defaults to the configured AUTHZEN_PDP_URL.

Output parameters:

- `metadata` (object)
- `metadata_url` (string)

### `authzen_evaluate` (~279 tokens)

Ask an OpenID AuthZEN 1.0 Policy Decision Point whether a subject may perform an action on a resource. Use this when the answer has to come from the PDP that actually governs the system, rather than from a policy pasted into the conversation. Returns the PDP's decision and any context it attached.

Input parameters:

- `action` (string, required): JSON object naming the action. AuthZEN requires "name"; "properties" is optional. Example: {"name":"read"}
- `context` (string): Optional JSON object of runtime context the policy may read — IP address, time of day, MFA strength. Example: {"ip":"10.0.0.7","mfa":"webauthn"}
- `pdp_url` (string): Override the configured AUTHZEN_PDP_URL for this call. Must be an absolute http(s) URL to an Access Evaluation endpoint.
- `resource` (string, required): JSON object identifying the target. AuthZEN requires "type" and "id"; "properties" is optional. Example: {"type":"document","id":"doc-1","properties":{"classification":"secret"}}
- `subject` (string, required): JSON object identifying the principal. AuthZEN requires "type" and "id"; "properties" is optional. Example: {"type":"user","id":"alice","properties":{"department":"sales"}}

Output parameters:

- `context` (null|array)
- `decision` (boolean)
- `pdp_url` (string)
- `request_id` (string)

### `authzen_evaluate_batch` (~328 tokens)

Ask an OpenID AuthZEN 1.0 PDP for several decisions in one round trip (the Access Evaluations API). Use this to answer "which of these may the subject do" — filtering a list of resources, or checking every action on one resource — instead of calling authzen_evaluate in a loop. Top-level subject/action/resource/context act as defaults that each entry may override.

Input parameters:

- `action` (string): Default JSON action for entries that omit one. Requires "name".
- `context` (string): Default JSON context object for entries that omit one.
- `evaluations` (string, required): JSON array of evaluation objects. Each may carry its own "subject", "action", "resource" and "context"; anything omitted falls back to the top-level argument of the same name. Example: [{"resource":{…
- `evaluations_semantic` (string): How the PDP should process the list. `execute_all` (default) evaluates every entry; `deny_on_first_deny` and `permit_on_first_permit` let the PDP stop early and return fewer decisions than there were…
- `pdp_url` (string): Override the configured AUTHZEN_PDP_URL for this call. Must point at an Access Evaluations (plural) endpoint.
- `resource` (string): Default JSON resource for entries that omit one. Requires "type" and "id".
- `subject` (string): Default JSON subject for entries that omit one. Requires "type" and "id".

Output parameters:

- `decisions` (null|array)
- `evaluations_semantic` (string)
- `pdp_url` (string)
- `request_id` (string)
- `truncated` (boolean)

### `evaluate_policy` (~292 tokens)

Evaluate a Rego policy module against an input document and optional data namespace. Runs in-process via OPA; no external service is contacted, and the built-ins that could contact one are disabled. Use this to author or debug a policy whose source you have. Returns the decision, whether the query was defined at all, the raw OPA result set, and any print() output.

Input parameters:

- `data_json` (string): JSON-encoded base document seeding the `data` namespace, for policies that read reference data.
- `input_json` (string): JSON-encoded input document — the `input` variable inside the policy.
- `query` (string, required): Rego query to evaluate, e.g. `data.example.allow` or `data.example.violations[_]`.
- `rego` (string, required): Rego source for the policy module. Must include a `package` declaration. Rego v1 syntax by default: rule bodies need `if`, and multi-value rules need `contains`.
- `rego_version` (string): Rego syntax version: `v1` (default) or `v0` for pre-OPA-1.0 policies written without `if`/`contains`.
- `trace` (boolean): Return a pretty-printed evaluation trace. Use this to find out why a rule did not fire; it is verbose, so leave it off until a result is surprising.

## Diagnostics

Captured diagnostic sections: Provenance. The full working is on the page: https://verifymcp.io/servers/kanywst-mcp-opa-authz/ghcr-io-kanywst-mcp-opa-authz-0-3-0#diagnostics

## Score history

- 2026-09-20: 44
- 2026-09-19: 44
- 2026-09-18: 43
- 2026-09-17: 40
- 2026-09-16: 40
- 2026-09-15: 40
- 2026-09-14: 40
- 2026-09-13: 40
- 2026-09-12: 40
- 2026-09-11: 40

## Common questions

### What is the io.github.kanywst/mcp-opa-authz server?

io.github.kanywst/mcp-opa-authz is listed in the public MCP registry as io.github.kanywst/mcp-opa-authz. Authorization answers from real policy code: evaluate Rego locally, or ask an AuthZEN 1.0 PDP. This page covers its container image (ghcr.io/kanywst/mcp-opa-authz:0.3.0).

### Is the io.github.kanywst/mcp-opa-authz server safe to use?

io.github.kanywst/mcp-opa-authz scores 44 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the io.github.kanywst/mcp-opa-authz server expose?

io.github.kanywst/mcp-opa-authz exposes 4 tools: authzen_discover, authzen_evaluate, authzen_evaluate_batch, evaluate_policy. Their descriptions and schemas cost roughly 1,017 tokens of context every time the server is loaded.

### Is the io.github.kanywst/mcp-opa-authz server still maintained?

io.github.kanywst/mcp-opa-authz is still listed as active in the MCP registry. We last reached this channel on 20 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

### What licence is the io.github.kanywst/mcp-opa-authz server under?

io.github.kanywst/mcp-opa-authz declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.

## Links

- Repository: https://github.com/kanywst/mcp-opa-authz
- Changelog RSS feed: https://verifymcp.io/servers/kanywst-mcp-opa-authz/ghcr-io-kanywst-mcp-opa-authz-0-3-0.xml
- Changelog JSON feed: https://verifymcp.io/servers/kanywst-mcp-opa-authz/ghcr-io-kanywst-mcp-opa-authz-0-3-0.json
- HTML version of this page: https://verifymcp.io/servers/kanywst-mcp-opa-authz/ghcr-io-kanywst-mcp-opa-authz-0-3-0