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 malloydata/publisher --skill malloy-gotchas-queriesgit clone --depth 1 https://github.com/malloydata/publisherWrote 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/malloydata/publisher/malloy-gotchas-queries)<a href="https://agentmods.dev/skills/malloydata/publisher/malloy-gotchas-queries"><img src="https://agentmods.dev/badge/skills/malloydata/publisher/malloy-gotchas-queries/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/malloydata/publisher/malloy-gotchas-queries"><img src="https://agentmods.dev/badge/skills/malloydata/publisher/malloy-gotchas-queries.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00048 | $0.02130 |
| Opus 5 | $0.00024 | $0.01065 |
| Sonnet 5 | $0.00010 | $0.00426 |
| Haiku 4.5 | $0.00005 | $0.00213 |
Grade A, and why
malloy-gotchas-queries 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 12d 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 — 192 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Query & View Gotchas
Read this before writing views or queries. These patterns cause most query errors.
Charts: ONE Aggregate Per View
Charts render only the first aggregate. Use exactly one aggregate per # bar_chart / # line_chart view.
// WRONG: revenue is ignored
# bar_chart
view: x is { group_by: status, aggregate: order_count, revenue }
// RIGHT: single aggregate
# bar_chart
view: x is { group_by: status, aggregate: revenue }
For multiple metrics: nest separate chart views in a # dashboard, or use y=['revenue','cost'] for multi-measure series.
Joined Fields in order_by: Must Alias First
// WRONG: compile error
view: x is { group_by: races.season_year, aggregate: pts, order_by: races.season_year }
// RIGHT: alias then reference
view: x is { group_by: yr is races.season_year, aggregate: pts, order_by: yr }
Any time you group_by a joined field, create an alias and use it in order_by.
having: vs where:: Aggregate Filters
// WRONG: "Aggregate expressions not allowed in where"
view: x is { group_by: cat, aggregate: n is count(), where: n > 10 }
// RIGHT
view: x is { group_by: cat, aggregate: n is count(), having: n > 10 }
where:filters rows BEFORE aggregation (dimensions/raw columns)having:filters AFTER aggregation (measures)
Aggregating Joined Fields: Method Syntax
// WRONG: compile error: "Join path is required for this calculation; use 'inventory_items.item_cost.sum()'"
measure: cogs is sum(inventory_items.item_cost)
// RIGHT: method syntax
measure: cogs is inventory_items.item_cost.sum()
sum, avg, min, and max over a dotted joined path all produce that compile error; the diagnostic message even tells you the exact fix. Don't worry about catching this in code review; the compiler does it for you.
Method syntax is for aggregates over a path. Scalar functions never take it.
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.
- 12d ago First seen · 192 lines · 48 tokens per session scan A 8c2759fd0f7d
malloy-gotchas-queries is a skill published in the GitHub repository malloydata/publisher (102 stars, last pushed today), licensed MIT. It adds 48 tokens to every session and 2,130 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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