# MCP Security Reviewer

> Use before connecting a new MCP server to your agent — produces a structured security review covering source, permissions, tools, network, and approvals.

- Skill: `oxbshw/mcp-security-reviewer` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add oxbshw/mcp-security-reviewer`
- Raw SKILL.md: https://api.skillmd.com/api/skills/oxbshw/mcp-security-reviewer/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: oxbshw (https://skillmd.com/u/oxbshw)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/oxbshw/mcp-security-reviewer

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# MCP Security Reviewer

## When to use
- A new MCP server is being added to an agent
- An MCP server version is being bumped
- An incident triggered a re-review

## Inputs
| Name | Type | Required | Notes |
|---|---|---|---|
| `repo_url` | string | yes | the MCP server's source |
| `version` | string | yes | tag or commit SHA being adopted |
| `intended_use` | string | yes | one paragraph: what we'll let it do |

## Workflow
1. **Source review**: clone at the pinned version; check for unexpected files / scripts
2. **Capabilities**: list every tool and resource exposed; map to risk levels (`references/mcp-risk-matrix.md`)
3. **Network**: identify outbound endpoints; document and assess each
4. **Permissions**: minimum required scopes / tokens; document over-permissions
5. **Output handling**: confirm the agent treats tool output as untrusted (sanitization, no execution)
6. **Approvals**: define which tools require human approval
7. **Produce filled `MCP_SERVER.md`** in `mcp/<server>.md`

## References
- [`references/mcp-risk-matrix.md`](references/mcp-risk-matrix.md)

## Success criteria
- All tools labelled by risk
- High/Critical tools gated by approval
- Pinned version (no `latest` / floating refs)
- Documented network egress

## Failure modes
- Source unavailable / un-pinnable → reject
- Discovered hidden tool not in docs → reject and report upstream