# subagentcitations.com — the Citation primitive

> Generalizes Anthropic's real Citations API response schema (char_location / page_location / content_block_location) into a durable, D1-backed, cross-site record any site in this family can create and reference.

## API
- GET /api/citations — list all citations, filterable by ?location_type= and ?source_site=
- GET /api/citations/:id — fetch one citation by id
- POST /api/citations — create or update a citation (gated by CITATIONS_WRITE_SECRET)
- GET /api/changes — newest-first change feed (?cursor=&limit=) for polling agents
- POST /mcp — Streamable-HTTP MCP endpoint (initialize / tools/list / tools/call get_citations); server card at /.well-known/mcp/server-card.json

## Grounding
Columns map 1:1 to Anthropic's real Citations API response schema (char_location / page_location / content_block_location, each with cited_text/document_index/document_title).
Canonical source: https://platform.claude.com/docs/en/build-with-claude/citations.md

## Family
This site is one of the Cloudflare Workers in the subagent*.com family. For the
live, machine-readable directory of every sibling domain, Cloudflare zone ID,
and worker binding, fetch:
https://subagentsubdomains.com/api/dns-zones

For a unified catalog of every API route across every primitive in the family:
https://subagentapi.com/api/catalog