Tool surface — Citra

Policy: few, powerful, obvious tools.

Tool	Role
read_pdf	Primary structured PDF read (text, tables, map, citations)
search_pdf	Literal retrieval with page/bbox locators
pdf_evidence	Follow-up ops: inspect / render / crop / OCR / regions (op enum)

Surfaces

Surface	Role
MCP	Agent tools over stdio
CLI	citra
SDK	@sylphx/citra/sdk

Rules

1. No near-duplicate vanity tools.
2. Advanced ops live inside pdf_evidence, not new tool names.
3. Fail closed on unsafe input / missing native.
4. Composition with siblings via host/public contracts only (Prism retired).