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enhance-plugins

enhance-plugins

github.com/agent-shAgent workflows1.0k82 installsUpdated 2d ago
Repository

About enhance-plugins

enhance-plugins is an agent skill for reviewing plugin structure, MCP tool schemas, and security patterns. It produces a Markdown report and can apply selected high-certainty fixes.

Key features

  1. 01Plugin structure checks
  2. 02MCP tool schema review
  3. 03Security pattern detection
  4. 04Markdown analysis reports
  5. 05High-certainty schema fixes

Use cases

  1. 01Reviewing a plugin before release
  2. 02Checking tool descriptions and schemas
  3. 03Finding security risks in plugin files

MCP support

The skill checks MCP configurations and tools exposed by plugins, including server patterns and security considerations.

Install

Copy the command and run it in a terminal.

$npx skills add https://github.com/agent-sh/agentsys --skill enhance-plugins

After installing, type/enhance-pluginsin Claude Code to confirm it loaded.

Details

From the project README

enhance-plugins

Analyze plugin structures, MCP tools, and security patterns against best practices.

Parse Arguments

const args = '$ARGUMENTS'.split(' ').filter(Boolean);
const targetPath = args.find(a => !a.startsWith('--')) || '.';
const fix = args.includes('--fix');

Plugin Locations

PlatformLocation
Claude Codeplugins/*/, .claude-plugin/plugin.json
OpenCode.opencode/plugins/, MCP in opencode.json
CodexMCP in ~/.codex/config.toml

Workflow

  1. Discover - Find plugins in plugins/ directory
  2. Load - Read plugin.json, agents, commands, skills
  3. Analyze - Run pattern checks by certainty level
  4. Report - Generate markdown output
  5. Fix - Apply auto-fixes if --fix (HIGH certainty only)

Detection Patterns

1. Tool Schema Design (HIGH)

Based on function calling best practices:

Required elements:

{
  "name": "verb_noun",
  "description": "What it does. When to use. What it returns.",
  "input_schema": {
    "type": "object",
    "properties": {
      "param": {
        "type": "string",
        "description": "Format and example"
      }
    },
    "required": ["param"],
    "additionalProperties": false
  }
}

The "Intern Test" - Can someone use this tool given only the description?

IssueCertaintyAuto-Fix
Missing additionalProperties: falseHIGHYes
Missing required arrayHIGHYes
Missing tool descriptionHIGHNo
Missing param descriptionsMEDIUMNo
Vague names (search, process)MEDIUMNo
2. Description Quality (HIGH)

Tool descriptions must include:

  • What the function does
  • When to use it (trigger context)
  • What it returns
// Bad - vague
"description": "Search for things"

// Good - complete
"description": "Search product catalog by keyword. Use for inventory queries or price checks. Returns matching products with prices."

Parameter descriptions must include:

  • Format expectations
  • Example values
  • Relationships to other params
// Bad
"query": { "type": "string" }

// Good
"query": {
  "type": "string",
  "description": "Search keywords. Supports AND/OR. Example: 'laptop AND gaming'"
}
3. Schema Structure (MEDIUM)
IssueWhy It Matters
Deep nesting (>2 levels)Reduces generation quality
Missing enums for constrained valuesAllows invalid states
No min/max on numbersUnbounded inputs
>20 tools per pluginIncreases error rates

Prefer flat structures:

// Bad - nested
{ "config": { "settings": { "timeout": 30 } } }

// Good - flat
{ "timeout_seconds": 30 }
4. Plugin Structure (HIGH)

Required files:

plugin-name/
├── .claude-plugin/
│   └── plugin.json      # name, version, description
├── commands/            # User-invokable commands
├── agents/              # Subagent definitions
├── skills/              # Reusable skill implementations
└── package.json         # Optional, for npm plugins

plugin.json validation:

  • name: lowercase, kebab-case
  • version: semver format (^\d+\.\d+\.\d+$)
  • description: explains what plugin provides

Version sync: plugin.json version must match package.json if present.

5. MCP Server Patterns (MEDIUM)

For plugins exposing MCP tools:

Transport types:

  • stdio - Standard I/O (most common)
  • http - HTTP/SSE transport

Configuration:

{
  "mcp": {
    "server-name": {
      "type": "local",
      "command": ["node", "path/to/server.js"],
      "environment": { "KEY": "value" },
      "enabled": true
    }
  }
}

Security principles:

  • User consent for data access
  • No transmission without approval
  • Tool descriptions are untrusted input
6. Security Patterns (HIGH)

HIGH Certainty issues:

PatternRiskDetection
Unrestricted BashCommand executiontools:.*Bash[^(]
Command injectionShell escape\${.*} in commands
Path traversalFile access\.\.\/ in paths
Hardcoded secretsCredential leakAPI keys, passwords

MEDIUM Certainty issues:

PatternRisk
Broad file accessData exfiltration
Missing input validationInjection attacks
No timeout on toolsResource exhaustion

Input validation required:

// Validate before execution
function validateToolInput(params, schema) {
  // Type validation
  // Range validation (min/max)
  // Enum validation
  // Format validation (regex patterns)
}
7. Error Handling (MEDIUM)

Tools should return structured errors:

{
  "type": "tool_result",
  "tool_use_id": "id",
  "content": "Error: [TYPE]. [WHAT]. [SUGGESTION].",
  "is_error": true
}

Retry guidance:

  • Transient (429, 503): exponential backoff
  • Validation (400): no retry, return error
  • Timeout: configurable, default 30s
8. Tool Count (LOW)

"Less-is-More" approach:

  • Research shows reducing tools improves accuracy by up to 89%
  • Limit to 3-5 relevant tools per task context
  • Consider dynamic tool loading for large toolsets

Auto-Fixes

IssueFix
Missing additionalPropertiesAdd "additionalProperties": false
Missing requiredAdd all properties to required array
Version mismatchSync plugin.json with package.json

Output Format

## Plugin Analysis: {name}

**Files scanned**: {count}

| Certainty | Count |
|-----------|-------|
| HIGH | {n} |
| MEDIUM | {n} |

### Tool Schema Issues
| Tool | Issue | Fix | Certainty |

### Structure Issues
| File | Issue | Certainty |

### Security Issues
| File | Line | Issue | Certainty |

Pattern Statistics

CategoryPatternsCertainty
Tool Schema5HIGH
Descriptions2HIGH
Schema Structure4MEDIUM
Plugin Structure3HIGH
MCP Patterns2MEDIUM
Security6HIGH/MEDIUM
Error Handling2MEDIUM
Tool Count1LOW
Total25-
### Schema Strictness ```json { "properties": { "path": { "type": "string" } } } ``` ```json { "properties": { "path": { "type": "string", "description": "File path" } }, "required": ["path"], "additionalProperties": false } ```
Tool Description

<bad_example>

"description": "Search for things"

</bad_example> <good_example>

"description": "Search product catalog by keyword. Use for inventory or price queries. Returns products with prices."

</good_example>

Security

<bad_example>

tools: Read, Bash  # Unrestricted

</bad_example> <good_example>

tools: Read, Bash(git:*)  # Scoped

</good_example>

References

  • agent-docs/FUNCTION-CALLING-TOOL-USE-REFERENCE.md - Tool schema, descriptions, security
  • agent-docs/CLAUDE-CODE-REFERENCE.md - Plugin structure, MCP config
  • agent-docs/OPENCODE-REFERENCE.md - OpenCode MCP integration
  • agent-docs/CODEX-REFERENCE.md - Codex MCP config

Constraints

  • Auto-fix only HIGH certainty issues
  • Security warnings are advisory - do not auto-fix
  • Preserve existing plugin.json fields
  • Never modify tool behavior, only schema definitions

Comments

Markdown supported