citature¹

15 questions · answered in full

Questions.

Each answer stands on its own and states its figure rather than pointing at a table, because the reader deciding whether to wire citature up is usually not a person.

What does citature do?
citature answers questions about food, supplements, substances and labels from primary US federal records, and returns each answer with the record it came from, that record's own version and dates, and a statement of what the answer does not cover. It is sold per call to AI agents over its own MCP endpoint. The product is not the data — the data is public — it is the answer with its receipt attached.
What does a call cost?
Of the 10 tools, 6 are free and carry no meter at all; the other 4 cost $0.05 per served answer. There is no subscription, no minimum and no marketplace in between, and a call bills at the rate of the tool it invokes.
Which tools are free, and why?
The lookups are free: food_lookup, supplement_lookup, drug_label_lookup, ingredient_resolve, substance_lookup, reference_amounts. Each restates a public record. The upstream serves it free, an open-data competitor carries more products than citature does, and charging for it would be charging for the part a caller can already get. A free tool never reaches the meter — not a charge of zero, no metering call on its path.
What is the paid half actually for?
The metered tools are rule_evaluate, enforcement_check, adverse_events, dietary_intake. What nobody else assembles is the join — one substance vocabulary across food, supplement and regulatory records, with every claim cited to a version of a document — and the evaluations and estimates built on it. That is what is priced.
Do I need a credential to try it?
No. Discovery and the free lookups answer without one, so an agent can register the server, list the tools and get real cited answers before anything is agreed. The priced tools require a bearer token issued for this resource, and so does a tool name the catalogue does not carry. A token that is presented is always checked, on a free tool as much as a priced one — an expired credential is refused rather than quietly served the free tier.
What comes back from a call?
A receipt: the answer itself, the citations behind it, the coverage caveats, the standing guardrails, the provenance of any join it made, and the schema version it was produced against. It arrives as structuredContent alongside the human-readable text, so an agent reads the citation and the coverage line without parsing prose.
Why is a survey answer a different shape?
Because there is no record it describes. An answer over a probability sample is an estimate, not a receipt: it carries the survey design in place of a record identity, and it states one of three things — a statistic, why one was withheld, or that citature has not built the data. An estimate is a sibling of a receipt, not a subtype of it, so the two cannot be confused for one another by a caller reading the type.
What happens if a call returns nothing?
It is not billed. The answer is produced first and the meter is touched only once it is in hand, so a request that produced no answer is never charged — and neither is an empty one. The asymmetry is deliberate: serving and failing to charge is citature's loss and acceptable; charging and failing to deliver is the buyer's and is not.
Can I check an answer without trusting citature?
That is the point of the receipt. A citation addresses the record rather than the fetch that landed it, and carries three clocks that are never collapsed: when citature retrieved it, what the release is current as of, and what the record's own author dated it. A citation is meant to be re-run by the reader with their own credential, so citature never puts a key in a cited URL.
Which records does it cite?
Primary federal records only, never an aggregator: fdc (USDA FoodData Central), dsld (NIH ODS Dietary Supplement Label Database), openfda (openFDA), nhanes (National Health and Nutrition Examination Survey (NHANES)), unii (FDA Substance Registration System (UNII)), ecfr (Electronic Code of Federal Regulations). Each dataset advances when its source publishes a release, and every answer carries the dates of the records behind it rather than a claim about the corpus.
Can citature tell me whether a product contains something?
It can tell you what a record declares. It cannot tell you what a product does not contain. A record that does not declare something is not a record declaring its absence. citature reports what a record states; it cannot report what a product does not contain, or what a population did not consume. There is no field anywhere in citature meaning "does not contain", because a label silent on an ingredient has said nothing at all.
Is a Daily Value the same as a Dietary Reference Intake?
No, and the distinction is regulatory rather than editorial. A Daily Value is a labelling reference from federal regulation, not a Dietary Reference Intake. citature carries no licensed source for Dietary Reference Intakes and does not estimate whether anyone meets a nutrient requirement.
Does citature give medical or nutritional advice?
No. Research over public records and product labels — not medical, nutritional, or safety advice. citature reports what the record says. It never renders a verdict, a pass/fail, a diagnosis, or a recommendation, and is not a substitute for a clinician.
Does citature hold data about people?
No, and it asks for none. Answers are product-, substance- or population-level only — foods, supplements, labels, substances, enforcement actions, and dietary intake as a weighted survey estimate. No answer returns or describes an individual person, and citature links no record to individually identifiable data.
How is a cross-source match reported?
By method, never silently, and there are four. Exact means one official key on both sides and nothing else. An official crosswalk is a mapping the source itself publishes. A barcode is an article number that manufacturers reuse, so a barcode join is reported as normalized and says so; ingredient text resolved to a registered substance is reported as fuzzy. Every method but exact carries a confidence, and a name match is reported as a name match, never as an identity.

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