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 Cratis/AI --skill cratis-arc-observable-query-httpgit clone --depth 1 https://github.com/Cratis/AIWrote 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/cratis/ai/cratis-arc-observable-query-http)<a href="https://agentmods.dev/skills/cratis/ai/cratis-arc-observable-query-http"><img src="https://agentmods.dev/badge/skills/cratis/ai/cratis-arc-observable-query-http/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/cratis/ai/cratis-arc-observable-query-http"><img src="https://agentmods.dev/badge/skills/cratis/ai/cratis-arc-observable-query-http.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 | $0.00082 | $0.02217 |
| Opus 5.5 | $0.00033 | $0.00887 |
| Sonnet 5.5 | $0.00016 | $0.00443 |
| Haiku 4.5 | $0.00008 | $0.00222 |
Grade A, and why
cratis-arc-observable-query-http scanned grade A with 1 finding 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 8d 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
description: Inspect a Cratis Arc observable query from a terminal with curl or another plain HTTP client — snapshot GET, waiting for the first result, Server-Sent Events streaming, and long polling, plus the exact query How it starts
The opening of the file, as written. The whole thing — 213 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Inspect an Arc observable query over HTTP
An observable query endpoint answers three different ways depending on how the request is made. Choose the transport first, then the command.
Verified product sources
| Package | Purpose |
|---|---|
Cratis.Arc.Core |
ObservableQueryHttp, ObservableQueryHandler, the demultiplexer routes |
Source symbols and signatures: every type, attribute and member this skill names exists in the product source.
This skill is read-only inspection of an endpoint the user already has; it neither implements the query nor changes any state.
How Arc picks the transport
For a query whose result is an ISubject<T> or IAsyncEnumerable<T>, the
handler decides in this order:
- WebSocket — the request is a WebSocket upgrade;
- Server-Sent Events — the
Acceptheader containstext/event-stream(case-insensitive); - plain HTTP — everything else, answered once and closed.
A plain curl sends neither, so it always lands on the third case — and there
the two result shapes part ways: an ISubject<T> query answers with one
QueryResult as described below, while an IAsyncEnumerable<T> query
answers HTTP 400 with { "message": "AsyncEnumerable queries require WebSocket connection" }
and never a QueryResult. Everything that follows on this page is about
ISubject<T>; inspect an IAsyncEnumerable<T> query over WebSocket.
Snapshot: the current value, once
curl "https://<host>/<api-prefix>/<route>"
The response is one JSON QueryResult (for an ISubject<T> query — see above).
⚠️ When the observable has not produced its first value yet, this returns HTTP 202 Accepted with a not-ready result — no exception, no data. That is a normal transient state (a subscription that has not emitted, a page past the end of the data), not a failure. A caller that treats 202 as an error is misreading a pending query as a crash.
Wait for the first result
curl "https://<host>/<api-prefix>/<route>?waitForFirstResult=true"
curl "https://<host>/<api-prefix>/<route>?waitForFirstResult=true&waitForFirstResultTimeout=10"
What ships with it
2 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.
- 8d ago Changed · +3 lines 814159967971
- 10d ago Changed 0b8ed2a7f133
- 11d ago Changed · +35 lines 729058ad4b16
- 17d ago Changed · +10 lines 63367a4afa92
- 1mo ago Changed · +7 lines 59e3ed1d7300
- 1mo ago First seen · 158 lines · 82 tokens per session scan A a57427814ea3
cratis-arc-observable-query-http is a skill published in the GitHub repository Cratis/AI (4 stars, last pushed today), licensed MIT. It adds 82 tokens to every session and 2,217 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-06.
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