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 skills add moonlight-lupin/agent-skills --skill endpoint-probegit clone --depth 1 https://github.com/moonlight-lupin/agent-skillsWrote 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/moonlight-lupin/agent-skills/endpoint-probe)<a href="https://agentmods.dev/skills/moonlight-lupin/agent-skills/endpoint-probe"><img src="https://agentmods.dev/badge/skills/moonlight-lupin/agent-skills/endpoint-probe/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/moonlight-lupin/agent-skills/endpoint-probe"><img src="https://agentmods.dev/badge/skills/moonlight-lupin/agent-skills/endpoint-probe.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00159 | $0.04693 |
| Opus 5.5 | $0.00064 | $0.01877 |
| Sonnet 5.5 | $0.00032 | $0.00939 |
| Haiku 4.5 | $0.00016 | $0.00469 |
Grade C, and why
endpoint-probe scanned grade C with 2 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 1mo 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.
Cloud metadata endpointhighServer-side request forgery
One request to 169.254.169.254 can return temporary IAM credentials.
21. **SSRF protection.** The probe blocks private/internal IP ranges (RFC1918, loopback, link-local, CGNAT `100.64/10`, ULA `fc00::/7`, IPv4-mapped IPv6 like `::ffff:127.0.0.1`) and cloud metadata endpoints (`169.254.169 Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
10. **Self-signed certs.** The script uses urllib which verifies certs by default. `PYTHONHTTPSVERIFY=0` does NOT affect urllib (it only affects `requests`/`httpx`). Self-signed targets are currently unsupported — use `- How it starts
The opening of the file, as written. The whole thing — 234 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Endpoint Probe
Probe a base URL to discover its API surface: type, auth, endpoints, rate limits, CORS, and server fingerprint.
When to Use
- User gives you a base URL and asks "what API is available?" or "what endpoints does this have?"
- You need to understand an undocumented or partially-documented API before building an integration
- User asks "how does this API authenticate?" or "what auth does this endpoint need?"
- You're evaluating a third-party service and need to map its API surface
- User says "discover", "probe", "explore", or "recon" an API endpoint
- User wants to know what tools an MCP server provides before configuring it
- User asks "what does this MCP server offer?" or "what tools does MCP server X have?"
Don't use for:
- Scraping HTML page content (use
website-scraping) - QA testing of known functionality (use a QA/testing skill)
- Configuring MCP servers (use an MCP configuration skill) — this skill discovers MCP server surfaces, it doesn't configure them
- Monitoring an API over time (this is a one-shot discovery tool)
Workflow
1. Run the probe script
python scripts/probe_api.py <base_url> [options]
Options:
| Flag | Description | Default |
|---|---|---|
--auth TOKEN |
Auth token/credential | none |
--auth-type |
bearer, basic, or apikey |
bearer |
--header "Key: Value" |
Custom header (repeatable) | none |
--timeout N |
Request timeout in seconds | 10 |
--json |
Output raw JSON instead of formatted report | off |
--no-guess |
Skip REST resource guessing | off |
--api-version v1 |
API version prefix for resource probing | none |
--mcp |
Probe as MCP server over HTTP (StreamableHTTP) | off |
--mcp-stdio |
Probe as MCP server over stdio (launch subprocess) | off |
--mcp-env "KEY=value" |
Env var for stdio MCP server (repeatable) | none |
--allow-private |
Allow probing private/internal IP addresses | off |
Examples:
# Basic probe — no auth
python scripts/probe_api.py https://api.example.com
# With Bearer token
python scripts/probe_api.py https://api.example.com --auth "tok_abc123"
# With API key (sends X-API-Key header)
python scripts/probe_api.py https://api.example.com --auth "key_xyz" --auth-type apikey
# Skip resource guessing (faster, less noisy)
python scripts/probe_api.py https://api.example.com --no-guess
# JSON output for programmatic use
python scripts/probe_api.py https://api.example.com --json
What ships with it
6 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 1mo ago First seen · 234 lines · 159 tokens per session scan C 8bb7742d6b76
endpoint-probe is a skill published in the GitHub repository moonlight-lupin/agent-skills (112 stars, last pushed 4d ago), licensed MIT. It adds 159 tokens to every session and 4,693 once invoked, about $0.0006 per session on Opus 5.5. A static security scan graded it C with 2 findings (cloud metadata endpoint, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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