T-04: Discovery & AI Access Layer

T-04: Discovery & AI Access Layer
W3C DCAT v3 (Data Catalog Vocabulary)
Dataset catalogue standard. CTH publishes a DCAT v3 catalogue at 
/api/catalogue listing all available climate datasets, their access conditions, formats, and ODRL usage policies. Registered with Google Dataset Search.
OpenAPI 3.1
Full API specification at 
/api/openapi.json. All endpoints documented with: security schemes (DID-based JWT), request/response schemas (JSON-LD), error codes, policy evaluation requirements. Enables direct agent integration without documentation scraping.
llms.txt
Machine-readable index at 
https://wiki.cleantechhub.net/llms.txt (and 
/llms-full.txt). Lists all framework pages with their purpose, so AI agents can navigate the wiki without embedding the full content. Updated automatically when framework pages change.
JSON-LD Context
Every framework concept (role, rule, credential type, standard) has a JSON-LD term at 
https://vocab.cleantechhub.net/climate/. Enables semantic interoperability with other climate data systems (e.g. UNTP registry, EU Commission linked data).
Agent Access Pattern
Recommended pattern for an AI agent integrating with the framework:
Fetch 
/llms.txt to identify relevant framework sections
Read specific wiki pages via BookStack API (read-only, no credential required for public pages)
Request a delegated 
cth:AgentCredential from the delegating human's session
Call 
POST /policy/evaluate with the intended action
If 
allow: true, proceed with the action using the policy token
PROV-O record is auto-generated by the API gateway (no agent action required)