Borrowing it
Nothing to install: this file belongs to CRJFisher/ariadne. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/CRJFisher/ariadne/main/.claude/skills/mcp-headless-test/SKILL.mdgit clone --depth 1 https://github.com/CRJFisher/ariadneWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/crjfisher/ariadne/mcp-headless-test)<a href="https://agentmods.dev/skills/crjfisher/ariadne/mcp-headless-test"><img src="https://agentmods.dev/badge/skills/crjfisher/ariadne/mcp-headless-test/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/crjfisher/ariadne/mcp-headless-test"><img src="https://agentmods.dev/badge/skills/crjfisher/ariadne/mcp-headless-test.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 3 findings, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Excessive Agency · line 104 Skill selects an external model or provider that may use a different account or billing plan than the operator expects. Undisclosed model switches can cause unexpected cost or quota consumption.Fix: Remove the model/provider override or disclose it prominently and require explicit operator approval before invoking an external coding CLI or billed model.
- high Excessive Agency · line 121 Skill selects an external model or provider that may use a different account or billing plan than the operator expects. Undisclosed model switches can cause unexpected cost or quota consumption.Fix: Remove the model/provider override or disclose it prominently and require explicit operator approval before invoking an external coding CLI or billed model.
- high Excessive Agency · line 140 Skill selects an external model or provider that may use a different account or billing plan than the operator expects. Undisclosed model switches can cause unexpected cost or quota consumption.Fix: Remove the model/provider override or disclose it prominently and require explicit operator approval before invoking an external coding CLI or billed model.
What 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 5.1 | $0.00045 | $0.01484 |
| Opus 5 | $0.00023 | $0.00742 |
| Sonnet 5 | $0.00009 | $0.00297 |
| Haiku 4.5 | $0.00005 | $0.00148 |
Grade A, and why
mcp-headless-test 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 10d 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 — 206 lines — stays where its author put it; the contents beside it link to each section on GitHub.
MCP Headless Test Pipeline
Purpose
Validate the Ariadne MCP server by running it with Claude Code in headless mode (claude -p). This tests the real user experience rather than just programmatic MCP client behavior.
Prerequisites
Before running tests, ensure:
- Claude Code CLI is installed and configured
- API key is set (either
ANTHROPIC_API_KEYenv var or Claude's configured key) - MCP package is built:
npm run build -w packages/mcp
Running the Tests
Quick Run
cd packages/mcp
./tests/claude-headless-test.sh
Verbose Mode (for debugging)
./tests/claude-headless-test.sh --verbose
Test Scenarios
The script runs 3 tests:
| Test | Name | What It Validates |
|---|---|---|
| 1 | Tool Discovery | Claude can see the list_entrypoints tool |
| 2 | Tool Invocation | Tool runs successfully on fixture code |
| 3 | Filtered Analysis | File/folder filtering parameters work |
Interpreting Results
Success Output
========================================
Ariadne MCP - Claude Headless Tests
========================================
[INFO] Checking prerequisites...
[INFO] All prerequisites met.
[INFO] Test 1: Tool Discovery
[INFO] Checking if Claude can see the list_entrypoints tool...
[INFO] PASS: Tool 'list_entrypoints' discovered
[INFO] Test 2: Tool Invocation
[INFO] Running list_entrypoints on fixture code...
[INFO] - Found 'entry point' in output
[INFO] PASS: Tool invocation succeeded
[INFO] Test 3: Filtered Analysis
[INFO] Testing file/folder filtering parameters...
[INFO] PASS: Filtered analysis completed
========================================
Test Summary
========================================
Total: 3
Passed: 3
Failed: 0
[INFO] All tests passed!
Failure Indicators
| Indicator | Meaning | Action |
|---|---|---|
Claude Code CLI not found |
claude command not in PATH |
Install Claude Code CLI |
MCP server not built |
Missing dist/server.js |
Run npm run build -w packages/mcp |
Tool 'list_entrypoints' not found |
Claude didn't discover the MCP tool | Check MCP config, server logs |
Tool invocation did not produce... |
Tool ran but output unexpected | Check if fixtures exist, review Claude's response |
FAIL: Filtered analysis... |
Folder filtering parameter not working | Check tool schema, parameter handling |
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.
- 10d ago First seen · 206 lines · 45 tokens per session scan A a4e6d14c78a3
mcp-headless-test is a skill published in the GitHub repository CRJFisher/ariadne (22 stars, last pushed 7d ago), licensed MIT. It adds 45 tokens to every session and 1,484 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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