Cost
Anthropic's guide says enabling citations adds some input tokens because of the prompt and the chunking, and that cited_text does not count toward output tokens. This card does not turn that into a dollar figure.
Home · Retrieval & Grounding · 10 · Citation & grounding check
Concept card · Retrieval & Grounding
Citation & grounding check
A citation and grounding check ties a claim in the reply to a source you actually retrieved.
Checking that a claim in the reply is tied to a source you actually retrieved.
What changed
Oct 18: First card. The picture ties a claim to a chunk, then cites the wrong chunk. Sources are Anthropic's citations guide and OpenAI's file search guide.
1 What it is
Anthropic's citations guide says you enable citations on a document and the response can attach a citation to a claim. The guide says the API extracts cited_text from the document, and that those citations contain valid pointers to the documents you provided. That statement is Anthropic's. A pointer is not a grade of the answer. OpenAI's file search guide says the message can include file_citation annotations with a file id and a filename. The support-docs answer bot on this site asks for a citations array in JSON. Anthropic's guide says citations cannot be used together with structured outputs, and that the API returns a 400 error if you enable both. The picture shows a claim with its source, then the same shape with the wrong source. It does not call either API.
2 Why it matters
Quality
A file id lets you open the file. It does not prove the sentence is in the chunk. On the support-docs answer bot, the template copies a sentence from the cited chunk. A model can name an id and write a sentence that chunk does not contain.
Risk
If one request needs both a JSON schema and Anthropic citations, the guide says the API returns a 400. Pick one on that request. A citation of a chunk you did not retrieve fails the check, even when the pointer is well formed.
3 How to apply · try today
Take one answer from the support-docs answer bot. Open the citation id. If the sentence is not in that chunk, the check fails.
Common mistake
Showing the citation and skipping the open-the-chunk step. Anthropic's pointer statement is about the document you sent, not about a file the model named from memory.
Self-check
The reply cites the hours chunk and says the refund window is 90 days. The hours chunk is about weekday hours. What failed?
Support-docs answer bot uses this concept in one build. The set on this tab is still the note below.
Coming soon. One support-bot answer, with the cited chunk opened and the sentence marked or marked missing.
Coming soon. How Anthropic attaches a citation to a document you sent, and how OpenAI's file search puts a file_citation on the message.
Questions
- What is a citation and grounding check?
- A citation and grounding check ties a claim in the reply to a source you actually retrieved.
- Does a citation prove the sentence is in the chunk?
- No. Anthropic's guide says the pointer refers to a document you provided. You still open the chunk and read the claim against it.
- Can Anthropic citations sit in the same request as structured outputs?
- Anthropic's guide says no. Enabling both returns a 400 error.