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-definegit 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-define)<a href="https://agentmods.dev/skills/malloydata/publisher/malloy-define"><img src="https://agentmods.dev/badge/skills/malloydata/publisher/malloy-define.svg" alt="Measured on agentmods" 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 | $0.00053 | $0.02459 |
| Opus 5 | $0.00026 | $0.01229 |
| Sonnet 5 | $0.00011 | $0.00492 |
| Haiku 4.5 | $0.00005 | $0.00246 |
Grade A, and why
malloy-define 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 7d 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 — 199 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Propose sources and definitions
This skill covers two consecutive activities when building or extending a Malloy semantic model:
Tool names are written bare here -
get_context,execute_query,search_malloy_docs. The exact prefixed name depends on the host surface; match each against the tools you actually have.
- Propose sources: the architectural blueprint (which sources, what grain).
- Propose definitions: the specific fields per base source (renames, dimensions, measures).
Both happen in conversation. Propose, let the user confirm or adjust, then carry the confirmed plan forward into the actual .malloy model. There is no separate plan-file store: keep the source plan and field proposals in the conversation, and write the model itself when the user has confirmed. See your modeling workflow for the broader picture.
Read the existing model first so you propose against what is really there. Use get_context with a plain-English description to inspect the current sources and fields and find the most relevant existing sources. Confirm the scope (which tables are in play) before proposing the source plan.
Propose a source plan
Goal: Propose the full source architecture for the tables in scope.
Base sources
One base source per table in scope. For each, specify:
| Source | Table | Grain | Primary Key | Role |
|---|---|---|---|---|
| orders | sales.orders | one row per order | order_id | Fact, transactions |
| customers | sales.customers | one row per customer | customer_id | Dimension, who |
| products | sales.products | one row per product | product_id | Dimension, what |
Computed sources
Computed sources are created from queries, not physical tables. Propose them when:
- Grain mismatch: the analytical scope requires a grain that no physical table provides (e.g., customer-level metrics from an order-grain table).
- Repeated aggregation patterns: the same group-by plus aggregate pattern would be used in multiple places.
- Cross-entity aggregations: inspecting the model and querying the data shows that an aggregate rolled up to a different entity would be reused.
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.
- 7d ago First seen · 199 lines · 53 tokens per session scan A 68b78355a91c
malloy-define is a skill published in the GitHub repository malloydata/publisher (100 stars, last pushed yesterday), licensed MIT. It adds 53 tokens to every session and 2,459 once invoked, about $0.0003 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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