Declare a fact

POST /v1/facts. Say what counts as one fact and how its values are chosen. resolve answers only for declared facts.

tckg does not guess identity. Which nodes are values of the same fact, and which value wins, are declared by you. Declarations are time-aware: resolve applies the declaration in force at as_of (or at rules_as_of).

Request

fact_key · string · required

The key nodes carry in fact_key.

key_fields · string[] · required

The fields that identify one instance of the fact.

policy · string · default: "latest_valid"

latest_valid (latest validity start wins), latest_observed (latest asserted_at wins), source_priority (first match in source_order wins), strict (two candidates is a refusal).

source_order · string[]

Required for source_priority.

Response

declared_at · timestamp

When the declaration took effect. Use it as rules_as_of when resolving past knowledge under this rule.

Request

curl -s -X POST $TCKG/v1/facts -H 'content-type: application/json' -d '{
  "fact_key": "belief:user:randy:NVDA:direction",
  "key_fields": ["space", "symbol"],
  "policy": "latest_valid"
}'

A node written with a fact_key that is not declared yet is still stored, with an undeclared_fact warning. Declare first when you can; otherwise declare later and resolve with rules_as_of.