# mcp-armor (oci · ghcr.io/studiomeyer-io/mcp-armor)

Security sidecar for MCP servers: 11 read-only control-plane tools for prompt-injection checks.

- Trust score: 41/100 (low)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-11-05

## Components

- oci · `ghcr.io/studiomeyer-io/mcp-armor`: 41/100 (this document), [markdown](https://verifymcp.io/servers/io-studiomeyer-armor/ghcr-io-studiomeyer-io-mcp-armor.md), [page](https://verifymcp.io/servers/io-studiomeyer-armor/ghcr-io-studiomeyer-io-mcp-armor)

## Channel facts

- Registry: `oci`
- Package: `ghcr.io/studiomeyer-io/mcp-armor`
- Version: `0.8.2`
- 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 2026-11-05.

- **Supply Chain Security**: 0/100
  - No malware scan is available for this kind of package: the supply-chain vendors we use do not cover it. This is a permanent gap in our coverage, not a finding about the package.
  - Known CVEs could not be checked: this image's dependency list comes from an SBOM its publisher attached, which nothing verifies, so we will not report it as a clean result.
  - Install-script risk not yet assessed.
  - Dependency health could not be checked: this image's dependency list comes from an SBOM its publisher attached. It names packages and versions but not whether each is deprecated, still maintained or linked to its source, so there is nothing we can fairly grade.
- **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 3 days ago).
  - Publishes a security disclosure policy (SECURITY.md).
- **Schema Quality & AI Usability**: 73/100
  - AI-judged instruction clarity (good).
  - Tool/resource definitions use about 736 tokens (~66/item across 11 items; 11 tools + 0 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 13/100
  - Stability observed for 4 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 75/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 24% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 11 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 11 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 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 mcp-armor server?

mcp-armor runs locally as a container image, launched with docker run --rm -i ghcr.io/studiomeyer-io/mcp-armor:0.8.2. 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 io-studiomeyer-armor -- docker run --rm -i ghcr.io/studiomeyer-io/mcp-armor:0.8.2
```

### Cursor

```json
{
  "mcpServers": {
    "io-studiomeyer-armor": {
      "command": "docker",
      "args": [
        "run",
        "--rm",
        "-i",
        "ghcr.io/studiomeyer-io/mcp-armor:0.8.2"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "io-studiomeyer-armor": {
      "command": "docker",
      "args": [
        "run",
        "--rm",
        "-i",
        "ghcr.io/studiomeyer-io/mcp-armor:0.8.2"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add io-studiomeyer-armor -- docker run --rm -i ghcr.io/studiomeyer-io/mcp-armor:0.8.2
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "io-studiomeyer-armor": {
      "type": "local",
      "command": [
        "docker",
        "run",
        "--rm",
        "-i",
        "ghcr.io/studiomeyer-io/mcp-armor:0.8.2"
      ],
      "enabled": true
    }
  }
}
```

### Hermes

```yaml
mcp_servers:
  io-studiomeyer-armor:
    command: "docker"
    args: ["run", "--rm", "-i", "ghcr.io/studiomeyer-io/mcp-armor:0.8.2"]
```

### Netclaw

```json
{
  "McpServers": {
    "io-studiomeyer-armor": {
      "Transport": "stdio",
      "Command": "docker",
      "Arguments": [
        "run",
        "--rm",
        "-i",
        "ghcr.io/studiomeyer-io/mcp-armor:0.8.2"
      ]
    }
  }
}
```

### Other

```json
{
  "mcpServers": {
    "io-studiomeyer-armor": {
      "command": "docker",
      "args": [
        "run",
        "--rm",
        "-i",
        "ghcr.io/studiomeyer-io/mcp-armor:0.8.2"
      ]
    }
  }
}
```

## 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.

### 2026-11-05 (score 41, +1)

No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-11-03 (score 40, +1)

No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-11-01 (score 39)

First indexed and scored.

## MCP tools (11)

### `armor_scan_payload` (~33 tokens)

Scan an arbitrary payload for prompt-injection patterns.

Input parameters:

- `direction` (string, required)
- `payload` (string, required)

### `armor_verify_manifest` (~62 tokens)

Verify Ed25519 signature over canonical-JSON form of a tools/list response.

Input parameters:

- `public_key_b64` (string, required)
- `signature_b64` (string, required)
- `signed_at_iso` (string)
- `tools_list_response` (object, required)

### `armor_list_blocked` (~37 tokens)

Read recent blocked tool calls from the in-memory ring buffer.

Input parameters:

- `limit` (integer)
- `since_iso` (string)

### `armor_get_policy` (~27 tokens)

Return the active policy: file path, rules, fail mode, scan flags, version.

### `armor_check_cve` (~60 tokens)

Look up exact product names or documented aliases in source-verified advisories; report affected, not_affected, or unknown version status. This does not prove scanner coverage.

Input parameters:

- `server_name` (string, required)
- `server_version` (string)

### `armor_simulate_attack` (~74 tokens)

Run an internal ARMOR-SIM pattern fixture through the scanner. Not a CVE exploit or product-remediation test. Legacy cve_id input is a migration alias only.

Input parameters:

- `cve_id` (string): Legacy simulation alias only; does not assert a CVE relationship.
- `simulation_id` (string)

### `armor_get_keystore` (~63 tokens)

v0.2 — List pinned TOFU maintainer public keys (server_name + fingerprint + pinned_at_iso). Read-only inspection of the keystore configured at sidecar startup (no caller-supplied path — operator-only via `--keystore` flag).

### `armor_verify_bundle` (~44 tokens)

v0.2 — Parse a cosign sigstore.json bundle and structurally verify the Rekor SignedEntryTimestamp shape. Offline.

Input parameters:

- `bundle_json` (string, required)

### `armor_rekor_lookup` (~78 tokens)

v0.2 — Query the Sigstore Rekor transparency log for inclusion of a manifest's artifact hash. Requires --features sigstore-bridge at build time. Network call.

Input parameters:

- `rekor_url` (string): Override Rekor endpoint; defaults to https://rekor.sigstore.dev
- `tools_list_response` (object, required)

### `armor_get_drift_history` (~119 tokens)

v0.5 Layer 7 — Inspect the tools-list schema-drift baselines persisted by `mcp-armor wrap`. Read-only. Optional `program` arg narrows the report to one upstream; omit it to list every pinned baseline. Closes the Rug-Pull / Silent-Redefinition threat class (Invariant Labs, CyberArk Full-Schema Poisoning).

Input parameters:

- `program` (string): When set, return the full per-tool fingerprint detail for one program. When omitted, return a summary list of every pinned baseline.

### `armor_scan_tools_list` (~139 tokens)

v0.8 Layer 8 — Scan a captured tools/list response for tool-description / full-schema poisoning (model-directed instructions hidden in tool descriptions, parameter schemas, enum values or defaults). Read-only; never spawns the upstream. Pass `tools_list` as the response object or a raw JSON string. Closes the first-sight Tool Poisoning (Invariant Labs) / Full-Schema Poisoning (CyberArk) / OWASP MCP03 class that Layer 7 drift (which only catches later changes) leaves open on the initial baseline.

Input parameters:

- `tools_list` (required): The tools/list response, as a JSON object or a JSON string.

## Diagnostics

Captured diagnostic sections: Provenance. The full working is on the page: https://verifymcp.io/servers/io-studiomeyer-armor/ghcr-io-studiomeyer-io-mcp-armor#diagnostics

## Score history

- 2026-11-05: 41
- 2026-11-04: 40
- 2026-11-03: 40
- 2026-11-02: 39
- 2026-11-01: 39

## Common questions

### What is the mcp-armor server?

mcp-armor is listed in the public MCP registry as io.studiomeyer/armor. Security sidecar for MCP servers: 11 read-only control-plane tools for prompt-injection checks. This page covers its container image (ghcr.io/studiomeyer-io/mcp-armor).

### Is the mcp-armor server safe to use?

mcp-armor scores 41 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 mcp-armor server expose?

mcp-armor exposes 11 tools: armor_scan_payload, armor_verify_manifest, armor_list_blocked, armor_get_policy, armor_check_cve, and 6 more. Their descriptions and schemas cost roughly 736 tokens of context every time the server is loaded.

### Is the mcp-armor server still maintained?

mcp-armor is still listed as active in the MCP registry. We last reached this channel on 5 November 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 mcp-armor server under?

mcp-armor 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

- GitHub Container Registry: https://ghcr.io/studiomeyer-io/mcp-armor
- Repository: https://github.com/studiomeyer-io/mcp-armor
- Changelog RSS feed: https://verifymcp.io/servers/io-studiomeyer-armor/ghcr-io-studiomeyer-io-mcp-armor.xml
- Changelog JSON feed: https://verifymcp.io/servers/io-studiomeyer-armor/ghcr-io-studiomeyer-io-mcp-armor.json
- HTML version of this page: https://verifymcp.io/servers/io-studiomeyer-armor/ghcr-io-studiomeyer-io-mcp-armor