Compare stored web observations without inventing materiality
Change Intelligence performs deterministic comparison of concrete stored root Web State observation pairs. It reports supported mechanical differences and abstains when the evidence cannot support the requested comparison.
Endpoint
GET /changes/example.com
The response is based on stored observations under the Change Intelligence contract. It should be read as evidence about differences between the compared observations, not as a claim about publisher intent, factual truth, or the business importance of the change.
Response states
changed
The supported comparison found one or more concrete differences.
unchanged
The compared supported state remained the same.
insufficient_history
There is not enough stored history for the requested comparison.
observation_gap
The stored evidence cannot support the requested consecutive comparison.
unknown
The service cannot support a stronger deterministic state from available evidence.
What can be compared
Supported comparisons can include text similarity, structured-data state, schema-type mask, normalized headers, word-count delta, internal and external link-count deltas, outbound-link fingerprint, AI-policy mask, canonical URL, final URL, and publisher-declaration state where evidence exists.
Evidence boundary
Change Intelligence is strongest when its answer can be reproduced from the same supported observation pair. If the required history is missing or discontinuous, the endpoint should preserve that uncertainty rather than manufacture a stronger conclusion.