A citation is a pointer, made durable.
Anthropic's real Citations API lets Claude "cite exact locations in source documents when answering questions about them" — every citation object in a Messages API response carries one of three location types, each with its own fields. This site takes that response shape and generalizes it past a single API call into a durable, linkable record any site in this family can create and reference. Read the exact schema on the citations-api concept page, quoted straight from Anthropic's own docs.
Plain text documents. start_char_index / end_char_index, 0-indexed, end exclusive. cited_text does not count towards output tokens.
PDF documents. start_page_number / end_page_number, 1-indexed, end exclusive — the only 1-indexed field in the whole schema.
Custom content documents. start_block_index / end_block_index, 0-indexed, end exclusive — used when a document is submitted as pre-chunked content blocks.
Live board
Real citations, seeded from quotes already used to ground sibling sites this session — not a mockup. See the live board →
Self-referential, on purpose
This is a citation-tracking site whose own seed data is itself citations. Three of the seed rows are pulled straight from subagentcontracts.com's own durability grounding page — the same <blockquote> text that site already cites to claude-tag's docs, now made a durable, queryable row here instead of living only inside an HTML tag. Two more are pulled from claude-tag/concepts/agent-identity.md, grounding a sibling site named subagentidentities.com (being built in parallel this session). And one row cites citations.md itself — the doc that defines this very primitive's schema, cited by the primitive it defines. See the full list on the live board, grouped by location type.
Who this is for
Any site in this family that quotes a source and wants that quote to be more than prose: POST /api/citations with a location_type, the exact cited_text, and either char, page, or block indices, and it becomes a durable row here — queryable by source_site, linkable by id, and groupable by location_type. See the API for the full contract.