Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/stacklok/toolhive/vmcp-reviewnpx skills add stacklok/toolhive --skill vmcp-reviewgit clone --depth 1 https://github.com/stacklok/toolhiveWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00044 | $0.00571 |
| Opus 5 | $0.00022 | $0.00285 |
| Sonnet 5 | $0.00009 | $0.00114 |
| Haiku 4.5 | $0.00004 | $0.00057 |
Grade A, and why
vmcp-review scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 61 lines — stays where its author put it; the contents beside it link to each section on GitHub.
vMCP Code Review
Purpose
Review code in pkg/vmcp/ and cmd/vmcp/ for known anti-patterns that increase cognitive load, create brittle dependencies, or undermine testability. This skill is used both for reviewing proposed changes and for auditing existing code.
Instructions
1. Determine Scope
Identify the files to review:
- If reviewing a PR or diff, examine only the changed files under
pkg/vmcp/andcmd/vmcp/ - If auditing a package, examine all
.gofiles in the target package - Skip files outside the vMCP codebase — this skill is vMCP-specific
2. Anti-Pattern Detection
For each file under review, check against the anti-patterns defined in .claude/rules/vmcp-anti-patterns.md (which is auto-loaded when vMCP files are read). Not every anti-pattern applies to every file — use judgment about which checks are relevant based on what the code does.
For each finding, classify severity:
- Must fix: The anti-pattern is being introduced or significantly expanded by this change
- Should fix: The anti-pattern exists in touched code and the change is a good opportunity to address it
- Note: The anti-pattern exists in nearby code but is not directly related to this change — flag for awareness only
3. Present Findings
Structure your report as:
## vMCP Review: [scope description]
### Must Fix
- **[Anti-pattern name]** in `path/to/file.go:line`: [What's wrong and what to do instead]
### Should Fix
- **[Anti-pattern name]** in `path/to/file.go:line`: [What's wrong and what to do instead]
### Notes
- **[Anti-pattern name]** in `path/to/file.go:line`: [Brief description, for awareness]
### Clean
No issues found for: [list anti-patterns that were checked and passed]
If no issues are found, say so explicitly — a clean review is valuable signal.
What This Skill Does NOT Cover
- General Go style issues (use
golangci-lintfor that) - Security vulnerabilities (use the security-advisor agent)
- Test quality (use the unit-test-writer agent)
- Non-vMCP code (use the general code-reviewer agent)
- Performance issues (unless they stem from an anti-pattern like repeated body parsing)
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 3d ago First seen · 61 lines · 44 tokens per session scan A 50ec95eb2343
vmcp-review is a skill published in the GitHub repository stacklok/toolhive (2,065 stars, last pushed yesterday), licensed Apache-2.0. It adds 44 tokens to every session and 571 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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mcp-redteam
Security audit of MCP servers. Safe mode (default) = source analysis + read-only probing. Active mode = controlled payload testing.
brin-check
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browser-control
Requires BROWSERAPIKEY in .env.
browser-skill
Imported from OpenClaw migration.
reviewing-code
Review code for quality, maintainability, and correctness. Use when reviewing pull requests, evaluating code changes, or providing feedback on implementations. Focuses on API design, patterns, and actionable feedback.