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mcp-security

Use when securing MCP servers, preventing prompt injection, implementing authorization, validating user input, or building secure multi-agent pipelines. Provides 5-layer defense architecture patterns.

Quality

77%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

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tessl review fix ./plugins/security-compliance/skills/mcp-security/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

68%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The body is token-efficient and well organized, covering the five layers with concrete RBAC/ABAC and context-propagation examples. Its main weaknesses are the non-executable sanitize/validate stub at the heart of the injection-prevention guidance and the absence of a sequenced, checkpointed workflow for applying the layers.

Suggestions

Replace the sanitize_input stub with an executable implementation (e.g., actual pattern stripping, length limiting, and a schema-validation call) so the skill's central defense is copy-paste ready.

Reframe the 5-Layer Defense Architecture as a sequenced workflow with validation checkpoints — e.g., validate input → check injection patterns → re-check authorization at each pipeline stage — rather than a flat category list.

Add brief ordering guidance or a short end-to-end request-handling example that shows the layers composed together, including what to do when a check fails.

DimensionReasoningScore

Conciseness

The body is lean and efficient — minimal prose, focused code blocks, and a checklist with no explanations of concepts Claude already knows; the one-line intro is the only mild redundancy, matching the "every token earns its place" anchor.

5 / 5

Actionability

The central defense mechanism is a stub — "def sanitize_input(...) -> str: ... pass" with comment placeholders instead of executable logic — and the ABAC example references undefined User/Resource types, fitting anchor 3 (pseudocode, missing key details) rather than 4.

3 / 5

Workflow Clarity

The "5-Layer Defense Architecture" reads as a categorized list rather than a sequenced workflow: there is no guidance on applying the layers in order and no validation checkpoints or error-recovery loops (only an end-state checklist), matching anchor 3.

3 / 5

Progressive Disclosure

As a single-file skill with no bundle files, it is cleanly sectioned with nothing buried, but at ~70 lines with thin treatment of layers 1–3 it sits just outside the under-50-line case that would warrant a 5, so anchor 4 applies.

4 / 5

Total

15

/

20

Passed

Description

75%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A strong description with an explicit third-person "Use when..." clause covering multiple natural trigger phrases and a clear niche in MCP/multi-agent security. The main weakness is a thin "what" clause — "Provides 5-layer defense architecture patterns" understates the concrete capabilities the body actually delivers.

DimensionReasoningScore

Specificity

The description names several concrete action areas ("securing MCP servers, preventing prompt injection, implementing authorization, validating user input") and states what it provides ("5-layer defense architecture patterns"), with minor gaps in coverage rather than the fully enumerated capabilities of a 5.

4 / 5

Completeness

It explicitly answers both "what" ("Provides 5-layer defense architecture patterns") and "when" ("Use when securing MCP servers, ... or building secure multi-agent pipelines") with concrete triggers, but the "what" clause is thinner than the multi-action "what" of the anchor-5 example.

4 / 5

Trigger Term Quality

Terms like "prompt injection", "MCP servers", "authorization", and "multi-agent pipelines" are phrases users would naturally say, but common synonyms and variations (e.g., tool security, access control, sandboxing) are missing, matching anchor 4 rather than 5.

4 / 5

Distinctiveness Conflict Risk

The MCP/multi-agent security niche is clearly distinguished with distinct triggers, but broader phrases like "implementing authorization" and "validating user input" carry minor overlap risk with general security or auth skills, so it fits anchor 4 rather than the minimal-conflict anchor 5.

4 / 5

Total

16

/

20

Passed

Validation

100%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository

jpoutrin/product-forge

Path

plugins/security-compliance/skills/mcp-security/SKILL.md

Reviewed

Table of Contents

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